JP2003291752A - On-vehicle electric power source controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent on-vehicle equipments 31-33 from being damaged or memory from getting cleared away caused by momentary interruption of a main electric power source voltage Vin, by a back-up of an electric power source voltage in the momentary interruption. <P>SOLUTION: In this controller, a back-up battery 8 is provided, the back-up is executed by the battery 8 when the main electric power source voltage Vin is lowered, a lowered condition continuing time Ts is detected, and whether the main electric power source voltage Vin is elevated or not within a time when the detected time Ts is shorter than the preset maximum momentary interruption time Tsmax, or whether a lowered condition is continued or not even after the maximum momentary interruption time Tsmax lapses, is detected. An electric power source voltage from the on-vehicle battery is output to the on-vehicle equipments and a back-up condition is released, when a detected result is the former, and the output of the power source voltage to the on-vehicle equipments is stopped when the detected result is the latter. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-vehicle power supply control device, and more particularly to an on-vehicle device which receives a power supply voltage from an on-vehicle battery, and at least a part of the on-vehicle battery is instantaneously lowered (instantaneously). The present invention relates to an in-vehicle power supply control device capable of backing up a power supply voltage at the time of a momentary power failure to prevent a part of the in-vehicle power supply control device from being destroyed or a memory being lost due to an instantaneous power failure.

[0002]

2. Description of the Related Art Generally, an automobile is not only equipped with a motor for an engine starter, a lamp, an air conditioner, etc., an in-vehicle device essential to the operation of the engine, safe driving of the automobile, the environment inside the vehicle, a car audio device, a car navigation system. It is equipped with various comfortable and convenient in-vehicle devices such as devices. The power supply for these on-vehicle devices is supplied by a power supply device including a generator (alternator) that operates with the operation of the engine and a battery (: secondary battery, for example, lead acid battery) charged by the generator. .

[0003]

By the way, the power supply voltage which is the output of the vehicle-mounted battery changes depending on the state of the vehicle,
A momentary interruption (: momentary power failure) can occur. For example, when the engine of the automobile is started, the power of the automobile is first turned on, and the switch of the starter motor is turned on after the power of the vehicle-mounted device is turned on. Therefore, the voltage drops momentarily and the voltage returns to normal after the engine is started. Therefore, the power supply voltage of the in-vehicle power supply control device is repeatedly increased within a short time, or dropped due to a momentary interruption, which in turn damages the in-vehicle power supply control device and causes the settings to be lost or malfunction. There was a risk that

In addition, when the engine of the automobile is stopped, the power source is often stopped immediately after the engine is stopped, and the power source of the vehicle-mounted device is instantaneously stopped. In the case of an in-vehicle device that requires a predetermined shutdown standby time when the power is stopped, the in-vehicle power supply control device may be damaged, and the settings may be lost or the device may malfunction.

In particular, recently, a hard disk drive using a hard disk drive as a storage means for a car navigation device or the like has appeared, but if the hard disk drive suffers a momentary drop in the power supply voltage during writing and reading, there is a strong possibility of failure.
However, in the past, no measures have been taken against such a momentary drop in the power supply voltage of the on-vehicle battery, and no particular consideration has been given to securing the shutdown standby time necessary for stopping the power supply. .

The present invention has been made to solve such a problem, and it is possible to instantaneously supply the power supply voltage of the on-vehicle battery to at least a part of the on-vehicle equipment supplied with the power supply voltage from the on-vehicle battery. Drop (instantaneous interruption: momentary power failure)
Sometimes the power supply voltage is backed up so that it is possible to prevent some in-vehicle devices from being destroyed or memory being lost due to a momentary power interruption. Detects it and stops the backup after the elapse of the specified shutdown waiting time,
Prevents wasteful consumption of the backup battery, and further
It is an object of the present invention to provide a new in-vehicle power supply control device that can secure a shutdown standby time when stopping backup.

[0007]

According to another aspect of the present invention, there is provided a vehicle-mounted power supply control device, which has a backup battery and which sends out the power supply voltage from the backup battery to the vehicle-mounted device when the power supply voltage from the vehicle-mounted battery decreases. While the state is formed, the lowered state duration time Ts is detected, and whether the power supply voltage from the vehicle-mounted battery rises while the lowered state duration time Ts is shorter than a preset maximum interruption time Tsmax. It is detected whether or not the lowering state continues even after the maximum disconnection time Tsmax has elapsed. If the result of the detection is the former, the power supply voltage from the on-vehicle battery is output to the on-vehicle electronic record and the backup state is canceled. Then
When the result of the above detection is the latter, the output of the power supply voltage to the vehicle-mounted device is stopped.

Therefore, according to the first aspect, when the power supply voltage from the vehicle-mounted battery drops, the power-supply voltage from the backup battery is supplied to the vehicle-mounted equipment, and whether or not there is a momentary interruption is determined by the power-supply voltage reduced state from the vehicle-mounted battery. Judgment is made by comparing the duration time Ts with the maximum interruption time Tsmax set as the maximum time in the range expected to be an interruption, and if the lowered state duration time Ts is less than the maximum moment Tsmax, it is determined as an interruption. The backup is stopped as the power supply voltage rises, and the power supply voltage from the on-vehicle battery is supplied to the on-vehicle equipment in the normal state, and conversely the reduced state duration Ts is the instantaneous maximum time T.
When it is smax or more, the power supply voltage from the vehicle-mounted battery is stopped and the supply of the power source voltage to the vehicle-mounted device is stopped (backup is stopped), so that it is possible to prevent the remaining charge of the backup battery from being unnecessarily reduced.

According to a sixth aspect of the present invention, there is provided a vehicle-mounted power supply control device, a power source voltage detecting means for detecting a power source voltage of a vehicle battery, a backup battery, and a reduced state duration time when the power source voltage output from the power source voltage detecting means decreases. A power source voltage drop determining means for determining whether or not the power source voltage continues to drop even after a preset time Tsmax has been exceeded after starting Ts timing, A switching state in which a power supply voltage is output and a switching state in which an output voltage from the backup battery is output,
At least a switching means for performing state switching control between a switching state in which no voltage is output is provided, and normally, the switching means is set to a state in which the power supply voltage from the vehicle-mounted battery is output, and when the power supply voltage from the vehicle-mounted battery decreases. When the switching means is switched to a state in which the output voltage from the backup battery is output and the power supply voltage continues to decrease even after the time period exceeding the instantaneous interruption maximum time Tsmax has elapsed, the switching means is switched to the voltage. It is characterized in that the switching state is set so as not to output.

Therefore, according to the on-vehicle power supply control device of the sixth aspect, when the power supply voltage from the on-vehicle battery drops, the power supply voltage from the backup battery is supplied to the on-vehicle equipment, and whether or not there is a momentary interruption is detected from the on-vehicle battery. Judgment is made by comparing the lowering state duration time Ts of the power supply voltage with the maximum momentary interruption time Tsmax set as the maximum time in the range expected to be the momentary interruption, and the lowering state duration time Ts is less than the maximum momentary time Tsmax. Then, the backup is stopped with the rise of the power supply voltage, and the power supply voltage from the on-vehicle battery is supplied to the on-vehicle equipment in the normal state.
If s is equal to or longer than the instantaneous maximum time Tsmax, it is recognized that the power supply voltage from the vehicle-mounted battery is stopped and the supply of the power supply voltage to the vehicle-mounted device is stopped (backup is stopped), and the remaining charge of the backup battery is unnecessarily reduced. Can be prevented.

According to another aspect of the present invention, there is provided an on-vehicle power supply control device, which includes a power supply distribution section for distributing both a power supply voltage from an on-vehicle battery and a power supply voltage from a backup battery to each on-vehicle device, and the on-vehicle device. Each of the power supply switching units receives a power supply voltage detecting means for detecting a power supply voltage of the vehicle-mounted battery, a power supply voltage from the vehicle-mounted battery and a power supply voltage from the backup battery, Of at least, and a switch means provided on the output side of the OR circuit, wherein the switch means is a built-in in-vehicle device corresponding to the power supply switching unit to which it belongs, When the power supply voltage output from the power supply voltage detecting means is lowered, the measurement of the lowered state duration time Ts is started, and the preset instantaneous interruption time Tsmax is exceeded. It is controlled by the power supply voltage drop determining means for determining whether or not the power supply voltage continues to decrease even after a lapse of time, and normally the switch means is turned on to output the output power supply voltage from the OR circuit. If the determination result that the power supply voltage continues to decrease even after a lapse of the time exceeding the instantaneous interruption maximum time from the power supply voltage decrease determination means causes the switch means to be turned off. It is characterized by

Therefore, according to the on-vehicle power supply control device of the ninth aspect, since there is an OR circuit for receiving the power supply voltage from the on-vehicle battery and the power supply voltage from the backup battery, the on-vehicle battery can be simply turned on at the subsequent stage. It is possible to form a state in which a backup battery is used to back up the decrease in the power supply voltage from, and whether or not there is a momentary interruption is determined by the duration time Ts of the decrease in the power supply voltage from the in-vehicle battery being the maximum time in the range expected to be a momentary interruption. Judgment is made by comparing with the maximum instantaneous interruption time Tsmax set as being present. If the lowered state duration time Ts is less than the maximum instantaneous time Tsmax, it is determined as an instantaneous interruption, backup is stopped with the rise of the power supply voltage, and the onboard battery The normal state in which the power supply voltage is supplied to the vehicle-mounted device is set, and conversely, the lowered state duration Ts is the instantaneous maximum time Ts.
If it is more than max, it is recognized that the power supply voltage from the on-board battery is stopped and the supply of the power supply voltage to the on-vehicle equipment is stopped (stopping the backup) to prevent the remaining charge of the backup battery from dropping unnecessarily. You can

An on-vehicle power supply control device according to a twelfth aspect of the present invention receives a power supply voltage detecting means for detecting a power supply voltage of an on-vehicle battery, a backup battery, a power supply voltage from the on-vehicle battery and a power supply voltage from the backup battery. Switching means for outputting the power supply voltage corresponding to the received control signal to the in-vehicle device, and a control circuit for sending out a control signal for controlling on / off of the power supply to the in-vehicle device supplied with the power supply voltage from the switching means. When the power supply voltage output from the power supply voltage detecting means decreases, the decrease state duration time Ts starts to be counted, and the power supply voltage decreases even after a preset instantaneous interruption time Tsmax has elapsed. At least a power supply voltage drop determining means for determining whether or not the power supply voltage from the vehicle-mounted battery is normally provided. When the power supply voltage from the vehicle-mounted battery drops, the switching means is switched to a state in which the output voltage from the backup battery is output, and the determination means outputs a time exceeding the instantaneous interruption maximum time Tsmax. When a determination result that the power supply voltage continues to decrease even after a lapse of time is generated, the switching means is set to a switching state in which no voltage is output.

Therefore, according to the on-vehicle power supply control device of the twelfth aspect, whether or not there is a momentary interruption is set by setting the duration Ts of the low state of the power supply voltage from the on-vehicle battery as the maximum time within the range expected to be a momentary interruption. Judgment is made by comparing with the instantaneous maximum interruption time Tsmax, and if the lowered state duration time Ts is less than the maximum instantaneous time Tsmax, it is determined as an instantaneous interruption, and the backup is stopped with the increase of the power supply voltage, and the power supply voltage from the vehicle battery is changed. When the reduced state duration time Ts is equal to or longer than the instantaneous maximum time Tsmax, it is recognized that the power supply voltage from the vehicle-mounted battery is stopped and a control signal for turning off the power is sent from the control circuit to the vehicle-mounted apparatus. At the same time, the supply of the power supply voltage from the switching means can be stopped (stopping the backup) to prevent the remaining charge of the backup battery from being unnecessarily reduced.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The in-vehicle power supply control device of the present invention basically has at least a backup battery, and when the power supply voltage from the in-vehicle battery is lowered, the power supply voltage from the backup battery is adjusted to the in-vehicle device. The lowering state duration time Ts is detected and the lowering state duration time Ts is shorter than the preset instantaneous interruption time Tsmax. It is detected whether or not the voltage has risen, or whether or not the voltage has continued to drop even after the maximum instantaneous interruption time Tsmax has elapsed. When the result of the above detection is the former, that is, when the power supply voltage from the vehicle-mounted battery rises to a predetermined voltage while the lowered state duration time Ts is shorter than the maximum interruption time Tsmax, the vehicle-mounted battery Request to output the power supply voltage from
Cancel the above backup state. If the result of the above detection is the latter, that is, if the lowered state continues even after the maximum instantaneous interruption time Tsmax has elapsed, control is performed to stop the output of the power supply voltage to the vehicle-mounted device. Note that the number of in-vehicle devices that supply the power supply voltage from the in-vehicle power supply control device may be one, or may be plural.

When the power supply voltage is supplied to the plurality of vehicle-mounted devices, the power supply voltage can be separately supplied to the plurality of vehicle-mounted devices, and the instantaneous interruption maximum time Tsmax is set for each of the plurality of vehicle-mounted devices. Correspondingly different time T
smaxn (n: 1, 2, ...) Is set, and a time Ts that exceeds the instantaneous interruption maximum time Tsmaxn set corresponding to each in-vehicle device is detected every time the power supply voltage continues to decrease. It is possible to stop the output of the voltage to the in-vehicle device corresponding to the maximum disconnection time Tsmaxn. With this configuration, the length of the instantaneous interruption maximum time Tsmax can be changed and set according to the degree to which it is necessary to determine whether or not the power supply voltage is stopped for each in-vehicle device.

Further, the time Ti (Ti: high continuation time after engine start) from when the power supply voltage from the vehicle-mounted battery rises to a predetermined value to when it falls is measured, and the power supply voltage drops. After that, when the backup state is formed later, the time count Ti is shorter or longer than the high continuous maximum time Timax after engine start,
The maximum instantaneous interruption time Tsmax for detecting whether or not the subsequent lowering state duration time Ts has been exceeded may be set to different values. Specifically, in the former case, Tsmax is set to a relatively long Tsmaxstart, and in the latter case, a relatively short Tsmaxnormal is set. This makes it possible to determine whether the decrease in the power supply voltage from the vehicle-mounted battery is a decrease after the engine is started or during normal operation, and the maximum instantaneous interruption time Tsmax is set between Tsmaxstart and Tsmaxnormal according to the result of the determination. It is possible to avoid stopping the supply of the power supply voltage to the in-vehicle device by erroneously determining that the decrease in the power supply voltage after the engine is started is the stop of the power supply from the normal vehicle-mounted battery. . Then, both Tsmaxstart and Tsmaxnormal have different values for each in-vehicle device, that is,
Tsmaxnormaln (n: 1, 2, 3, ...), Tsmax
Different values may be set, such as startn (n: 1, 2, 3, ...).

Further, when it is detected that the lowered state continuation time Ts has continued even after the preset maximum instantaneous interruption time Tsmax or Tsmaxn has passed, the output of the power supply voltage to the in-vehicle device is output. Stop. In that case, the stop may be performed after the shutdown waiting time Tw has elapsed from the detection time. By doing this, the voltage supply time from the backup battery can be reduced,
It is possible to prevent wasteful consumption of the backup battery.

It is preferable to use a secondary battery as the backup battery, and it is preferable to normally keep the state of being charged by the power source voltage from the vehicle-mounted battery and supply the output power source voltage to the vehicle-mounted device at the time of backup. . However, other types of batteries may be used. In addition, the in-vehicle power supply control device is composed of one power distribution unit that distributes both the main power supply voltage and the backup power supply voltage to each in-vehicle device, and a plurality of power supply switching units provided corresponding to each in-vehicle device. The main power supply voltage or the backup power supply voltage is supplied to the in-vehicle device via each power supply switching unit, and the control of each power supply switching unit is performed by the CPU for the in-vehicle device corresponding to the power supply switching unit. There may be an embodiment in which it is done. A concrete embodiment of the above-described basic form of the vehicle-mounted power supply control device of the present invention will be described in the section of the following embodiment.

[0020]

The present invention will be described in detail below with reference to the illustrated embodiments. 1 (A), (B) and FIG. 2 are for explaining a first embodiment of the on-vehicle power supply control device of the present invention.
(A) is a schematic system diagram of an electric system in an automobile, (B) is a schematic configuration diagram of an in-vehicle power supply control device, and FIGS. 2 and 3 are flowcharts showing an operation of the in-vehicle power supply control device.

First, the electric system in the automobile will be described with reference to FIG. In the drawing, reference numeral 1a denotes an on-vehicle power supply control device which detects a power supply voltage (main power supply voltage Vin) of an on-vehicle battery (main power supply) 2 and adjusts the power supply voltage to the on-vehicle devices 31 to 33 according to the detection result. Output. The specific content of the adjustment will be described later. In addition, 3a is an in-vehicle electric device (for example, a lamp, etc.), 3b is an engine control computer, 3c is a starter motor, and these are not the targets of control by the in-vehicle power supply control device 1a.

Of the in-vehicle devices 31 to 33 whose power supply voltage is to be adjusted by the in-vehicle power supply control device 1a, 31 is a car audio device, 32 is a car navigation device, and 33 is a car navigation device.
Is a security system.

Next, the structure of the on-vehicle power supply control device 1a will be described with reference to FIG. A CPU (central processing unit) 4 controls the inside of the vehicle-mounted power supply control device 1a. 5 is RO
M (read only memory) stores a program executed by the CPU 4 and the like. A CPU 6 performs temporary storage necessary when the CPU 4 executes the program stored in the ROM 5.

Reference numeral 7 denotes a main power supply voltage Vi of the on-vehicle battery 2.
An A / D converter for detecting n and converting it into a digital signal, which inputs the output digital signal to the CPU 4, corresponds to the power supply voltage detecting means in the claims. The output 1 is connected to the power supply lines of the in-vehicle device (car audio device) 31, the output 2 is connected to the in-vehicle device (car navigation device) 32, and the output 3 is connected to the power supply line of the in-vehicle device (security system) 33.

Reference numeral 8 denotes a backup battery (backup power source), which is a secondary battery and is charged or discharged. SW1 to SW3 are switches, which are switch-controlled by a switching control signal from the CPU 4, and are the power supply voltage of the main power supply (vehicle battery) 2, that is, the main power supply voltage Vin and the backup power supply (backup battery) 8, that is, bank up. One of the power supply voltage designated by the switching control signal is output from the outputs 1 to 3, or the output of the power supply voltage from the outputs 1 to 3 is stopped.

Next, the control operation executed by the CPU 4 will be described with reference to FIGS. Incidentally, the switches SW1 to SW3 are in a normal state in an initial state, that is, in a switching state in which the power source voltage Vin of the main power source 2 is output from the outputs 1 to 3, and the power source of the backup power source 8 is applied by applying a switching control signal. A switching state in which a voltage is supplied to the outputs 1 to 3 (backup switching state) and a switching state in which neither the main power supply voltage Vin nor the backup power supply voltage is supplied (non-output switching state) can be formed. First, the control operation in normal time will be described with reference to FIG.

(1) "Vin drop?" First, the main power supply voltage Vin is detected (the detection output of the A / D converter 7 is taken in), and the detected power supply voltage V is detected.
It is determined whether or not in has decreased. Specifically, it is determined whether or not there is a drop equal to or higher than the drop allowance fine voltage ΔVin set as the maximum voltage allowed to drop. If the determination result is No, that is, the main power supply voltage Vin
If no decrease occurs, this determination is repeated until a determination result of Yes is obtained.

(2) "Ts timer activation" If the result of the determination in step (1) is Yes,
Immediately, the Ts timer that measures the duration Ts of the lowered state of the main power supply voltage Vin is started. That is, the Ts timer starts counting the lowered state duration time Ts. (3) "Switch to backup power supply" After step (2), switch to backup power supply.
Specifically, the switches SW1 to SW3 are switched to output the backup power supply voltage) to the onboard devices 31 to 33 so that the onboard devices 31 to 33 receive the backup battery power supply voltage. This backup is performed simultaneously for outputs 1 to 3 in parallel.

(4) "Ts>Tsmax1?" Then, the maximum state Ts of the in-vehicle device (car audio device) 31 connected to the output 1 with the lowered state duration Ts
It is determined whether it is longer than max1. By the way, the maximum interruption time Tsmax is a time set as a reference for determining whether or not there is an interruption so that when it is shorter than that, it is determined as an interruption. Therefore, the lowered state duration Ts is Tsma.
If it is shorter than x, it is recognized as a momentary interruption, and if longer than this, it is not a momentary interruption but the power supply voltage Vi of the main power supply (vehicle battery)
It is recognized as the time that can be recognized as the supply stop of n.

The maximum interruption time Tsmax is set to a different value depending on the type of the vehicle-mounted device. That is, Tsmax1 for the in-vehicle device 31 and Tsmax for the in-vehicle device 32.
smax2 and Tsmax3 for the in-vehicle device 33, which are different from each other (in this example, Tsmax1 <Tsmax2 <Tsmax
3) is set. As described above, the length of the instantaneous interruption maximum time Tsmax is set according to the difference in the valid criteria for determining whether or not the power supply voltage is stopped for each of the in-vehicle devices 31, 32, and 33, as described above. This is because it can be set by changing. That is, some in-vehicle devices are damaged by short interruptions, and some are not damaged by relatively long interruptions. Time T
It is possible to set smax.

It should be noted that the instantaneous interruption maximum time Tsmax of the vehicle-mounted device (car audio device) 31 connected to the output 1 is Tsmax.
1, the maximum instantaneous interruption time Tsmax of the vehicle-mounted device (car navigation device) 32 connected to the output 2 is Tsmax2, the output 3
The maximum interruption time Tsmax of the vehicle-mounted device (security system) 33 connected to is Tsmax3. (5) “Vin drop?” When the result of the determination in step (4) is No, it is determined whether the power supply voltage Vin has dropped. This is nothing but the determination as to whether or not the power supply voltage drop state continues, and when the determination result is Yes, the above step (4) is performed.
Return to.

(6) "Switch to main power supply" If the result of the determination in step (5) is No, that is, the main power supply voltage Vin has returned to the original value, the power supply voltage Vin drops [step (1)]. Vin drop detected in 1.) can be said to be due to a momentary interruption.
The power supply for supplying the power supply voltage to the power supplies 1 to 33 is switched from the backup power supply 8 to the main power supply (vehicle-mounted battery) 2. Then, it returns to step (1). (7) "Power supply stop of in-vehicle device 31" If the determination result of step (4) is Yes, in-vehicle device 3
The supply of the power supply voltage to 1 is stopped, that is, the supply of the power supply voltage from the output 1 is stopped. Specifically, the switch SW1 is set to a switching state in which neither the main power supply voltage Vin nor the power supply voltage of the backup battery 8 is output. As a result, the operation of the vehicle-mounted device 31 is stopped.

(8) "Ts>Tsmax2?" Next, it is determined whether or not the lowered state duration time Ts is longer than the instantaneous interruption maximum time Tsmax2 of the vehicle-mounted device 32 (car navigation device) connected to the output 2. (9) “Vin drop?” When the result of the determination in step (8) is No, it is determined whether the power supply voltage Vin has dropped. This is nothing but the judgment of whether or not the decrease in the power supply voltage Vin [the decrease detected in the above step (1)] is continuing. If the result of the judgment is Yes, the process returns to the above step (8), If the result of this determination is No, the operation proceeds to step (6) above, where the main power supply 2 supplies the power supply voltage Vin to the on-vehicle devices 31 to 33.
Is switched to the state in which is supplied.

(10) "Power supply stop of in-vehicle device 32" If the determination result in step (8) is Yes, the in-vehicle device 3
2 is stopped, that is, the supply of power supply voltage from the output 2 is stopped. Specifically, the switch SW2 is set to a switching state in which neither the main power supply voltage Vin nor the backup power supply voltage is output. As a result, the in-vehicle device 32 stops operating. (11) “Ts> Tsmax3?” Then, the lowered state duration time Ts is the instantaneous interruption maximum time T of the vehicle-mounted device 33 (security system) connected to the output 3.
It is determined whether it is longer than smax3.

(12) "Vin drop?" If the judgment result of the step (11) is No, it is judged whether the power supply voltage Vin has dropped. This is nothing but the determination as to whether or not the reduced state of the power supply voltage Vin is continued. If the determination result is Yes, the process returns to step (8). If the determination result is No, the above step (8) is performed. Proceed to 6), from the main power source to each on-vehicle device 31-33.
The power supply voltage Vin is switched to the state where the power supply voltage Vin is supplied to.

(13) "Power supply stop of in-vehicle device 33" If the determination result in step (8) is Yes, the in-vehicle device 3
The supply of the power supply voltage to 2 is stopped, that is, the supply of the power supply voltage from the output 3 is stopped. Specifically, the switch SW3 is set to a switching state in which neither the main power supply voltage Vin nor the power supply voltage of the backup battery 8 is output. As a result, the in-vehicle device 33 stops operating, that is, the end. still,
In the case of the on-vehicle power supply control device that is also adapted to perform the operation of the flow shown in FIG. 4 which will be described later, the process proceeds to step (21) of the flow.

In such a vehicle-mounted power supply control device,
The main power supply voltage Vin detected by the A / D converter 7, which is the power supply voltage detecting means, is detected, and it is determined whether or not there is a decrease. If there is no decrease, the normal state, that is,
Each of the switches SW1 to SW3 is set to a switching state in which the main power supply voltage Vin is directly sent from each of the outputs 1 to 3 to each of the vehicle-mounted devices 31 to 33. Further, when the power supply voltage is decreased, the measurement of the decreased state continuation time Ts which is the elapsed time of the decreased state is started, and further the backup is started,
The power supply voltage from the backup battery 8 is supplied to the vehicle-mounted devices 31 to 33 as the power supply voltage. Therefore,
Even if a temporary drop in the main power supply voltage Vin occurs, it is possible to prevent the in-vehicle devices 31 to 33 from being damaged or causing a malfunction.

When the lowered state duration time Ts exceeds the instantaneous interruption maximum time Tsmax1 of the vehicle-mounted device 31 (car audio device) which receives the power supply voltage from the output 1, it is determined to be an instantaneous interruption (until tired of the car audio device). Then, the supply of the power supply voltage to the output 1 (the supply of the power supply voltage from the backup power supply 8) is stopped. This allows
Although the power supply voltage Vin is stopped, the power supply voltage is continuously supplied from the backup power supply 8 and the power of the backup power supply 8 is wastefully consumed.

Further, the lowered state duration Ts is output 2
When the maximum interruption time Tsmax2 of the vehicle-mounted device 32 (car navigation device) that receives the power supply voltage from the Supply (supply of power supply voltage from the backup power supply 8) is stopped. As a result, although the power supply voltage Vin is stopped, the power supply voltage is continuously supplied from the backup power supply 8 to the vehicle-mounted device 32 (car navigation device), and the power of the backup battery 8 is wasted, resulting in meaningless reduction of the remaining charge amount. The waste generated can be eliminated.

Further, the lowered state duration time Ts is output 3
When the maximum power interruption time Tsmax3 of the in-vehicle device 33 (security system) that receives the power supply voltage from the (Supply of power supply voltage from backup power supply 8) is stopped. As a result, although the power supply voltage Vin is stopped, the backup power supply 8
Since the power supply voltage is continuously supplied from the vehicle to the vehicle-mounted device 33 (security system), the power of the backup power supply 8 is wastefully consumed, and it is possible to eliminate the waste of meaningless reduction of the remaining charge amount. Then, when the power supply voltage Vin is restored, it returns to the normal state. That is, it returns to the original operating state in which the vehicle-mounted devices 31 to 33 are driven by the main power supply voltage Vin.

FIGS. 3A and 3B show a power supply voltage Vin (input to the in-vehicle power supply control device 1a) which is an output of the main power supply (in-vehicle battery 2) and an output from the in-vehicle power supply power supply control device 1a. Power supply voltage (this in-vehicle power supply control device 1
3A is a waveform diagram showing an output), and FIG. 3A shows a case where the lowered state duration time Ts does not exceed the maximum interruption time Tsmax, and FIG. The case where the time Tsmax is exceeded is shown. According to the in-vehicle power supply control device 1a, as shown in FIG. 3A, even if the power supply voltage Vin drops for a short time (Ts <Tsmax), the output from the in-vehicle power supply control device 1a is backed up by the backup power supply 8. The voltage does not drop.

Further, as shown in FIG. 3B, when the power supply voltage Vin is stopped, the supply of the power supply voltage from the backup battery 8 is stopped after the lapse of the maximum interruption time Tsmax. Therefore, in the case of a momentary interruption, the backup can be performed, then the normal state is restored, and in the case of stopping the power supply voltage Vin, the backup can be stopped after the elapse of the maximum interruption time Tsmax.

4 and 5 are for explaining the operation of the modified example of the embodiment 1a shown in FIGS. 1 to 3, FIG. 4 is a flowchart thereof, and FIGS. 5A to 5C are main. FIG. 5A is a waveform diagram showing the power supply voltage Vin that is the output of the power supply (vehicle-mounted battery) 2 and the output power supply voltage that is output from the vehicle-mounted power source power supply control device 1 a. FIG. <When the high continuation maximum time Timax after engine start, Ts <Tsmax, which will be described later, FIG. 5B shows the case where high continuation time Ti after engine start Ti <high continuation maximum time after engine start Timax, Ts> Tsmax,
(C) shows the case where high continuation time Ti after engine start> high continuation maximum time Timax after engine start and Ts <Tsmax.

In the present modification, the instantaneous interruption that is inevitably caused when the engine is started is lowered by the drop of the power supply voltage Vin [see FIG. 5 (A)], and when the supply of the power supply voltage from the vehicle battery is stopped, The voltage supply (backup) is stopped accordingly (see FIG. 5B).
It is a thing.

That is, to decrease the main power supply voltage Vin,
The supply of the power supply voltage Vin is stopped, and the instantaneous interruption that is inevitably generated when the engine is started. When the supply of the power supply voltage Vin is stopped, it is necessary to stop the supply of the power supply voltage Vin. It is necessary to back up the momentary interruption that occurs at the time of starting and to supply the original power supply voltage Vin after the momentary interruption.
This modification is to meet the need.

In this modification, the circuit configuration is common to that of the embodiment 1a shown in FIGS. 1 to 3, and the operation program is the program shown in FIG. 3 with the program shown in FIG. 4 added. Since only the program is different, the illustration and description of the circuit configuration are omitted. The operation of the modified example will be described below with reference to FIG. The switches SW1 to SW3 are in the normal state in the initial state,
That is, the switching state in which the main power supply voltage Vin is output from the outputs 1 to 3 is maintained, and the switching state in which the backup power supply voltage is supplied to the outputs 1 to 3 by applying the switching control signal (backup switching state) or The switching state (non-output switching state) in which neither the main power supply voltage Vin nor the backup power supply voltage is supplied can be formed.

(21) "Vin rise?" After starting the engine, first, the main power supply voltage Vin is detected (the detection output of the A / D converter 7 is taken in), and it is determined whether or not the power supply voltage Vin is rising. To do. In the operation of this modified example, first, it is indispensable to detect the rise of the main power supply voltage Vin, and therefore, first, it is detected whether or not the power supply voltage Vin is rising. When the determination result is No, the determination is repeated until the determination result of Yes is obtained.

(22) "Ti timer activation" If the determination result of the above step (21) is Yes, that is, if the power supply voltage Vin rises, the power supply voltage V is immediately reached.
By starting a Ti timer that measures a high duration time Ti after engine start, which is an elapsed time after the rise of in, the timing of the high duration time Ti after engine start is started. (23) “Power-on of in-vehicle devices 31 to 33” At the same time when the high duration time Ti after engine start is started, the power of all in-vehicle devices 31 to 33 is turned on.

(24) "Vin drop?" Next, it is determined whether the power supply voltage Vin has dropped. When the determination result is No, the determination is repeated until the determination result of Yes is obtained. (25) “Ti Timer Stop” When the result of the determination in the step (24) is Yes, the timing of the high continuation time Ti after engine start by the Ti timer is stopped.

(26) "Ti <Timax?" The high continuation time Ti after starting the engine is compared with the high continuation maximum time Timax after starting the engine to determine whether or not the Ti is smaller than Timax. High continuation maximum time at startup Tima
x is a time Ti until the power supply voltage Vin after the start-up falls after the start-up, which serves as a reference for determining that the engine has been started when the time is shorter than that in order to determine whether or not the engine has been started. . Therefore, if the high continuation time Ti after starting is shorter than the maximum high continuation time Timax after starting, it is determined that the engine has started, and the high continuation time T after starting T
When i is longer than the maximum continuous high time Timax after starting, it is determined that it is not after starting the engine.

(27) "Setting Tsmaxstart" If the result of the determination in step (26) is Yes, that is, if Ti <Timax, the engine is starting and the power supply voltage Vin is lowered after the engine is started. Tsmaxstart, that is, T
Set smaxstart1,2,3. Tsmaxstart1 is an in-vehicle device (car audio device) 31 connected to the output 1
Tsmaxstart2 for Tsmaxstart3 for in-vehicle equipment (car navigation device) 32 connected to output 2
Is a comparison reference for the in-vehicle device (security system) 33 connected to the output 3. In this way, the in-vehicle device 3
The reason why the value of Tsmaxstart is changed depending on Nos. 1 to 33 is to be able to cope with the difference in the characteristics of the vehicle-mounted devices 31 to 33 with respect to the instantaneous interruption.

(28) "Tsmaxnormal setting" If the determination result of the step (26) is No, that is, if Ti> Timax, it means that the engine is not started, that is, normal (Normal), In this normal case, Tsmaxnormal is used as a comparison reference in the comparison for determining whether there is a momentary interruption or a power supply stop for the time Ts during which the power supply voltage Vin decreases, that is,
Set Tsmaxnormal1,2,3. Tsmaxnormal1
Is an in-vehicle device (car audio device) connected to output 1
Tsmaxnormal2 for 31 is Tsmaxnor for in-vehicle equipment (car navigation device) 32 connected to output 2
mal3 is a comparison standard for an in-vehicle device (security system) connected to the output 3. In this way, the in-vehicle device 3
The reason why the value of Tsmaxnormal is changed according to 1 to 33 is to enable to cope with the difference in the characteristics of the vehicle-mounted devices 31 to 33 with respect to the instantaneous interruption.

(29) "Activation of Ts timer" Next, the lowering state duration time Ts of the main power supply voltage Vin
Start the Ts timer that keeps time. That is, the timing of Ts is started. (30) "Switch to backup power supply" Next, the power supply voltage supplied to the on-vehicle devices 31 to 33 through the outputs 1 to 3 is switched to the power supply voltage from the backup power supply 8. That is, the backup switching state is set.

(31) "Ts>Tsmax1?" Next, it is determined whether or not the lowered state duration time Ts exceeds the reference Tsmax1 for the vehicle-mounted device (car audio device) 31. As described above, the reference Tsmax1 is Tsmaxstart1, 2, set in step (27) when the determination result in step (26) is Yes.
Tsmaxstart1 out of 3, and in the case of No, Tsmaxnormal set in step (28)
Of 1, 2, and 3, it becomes Tsmaxnormal1. (32) “Vin lowered?” When the result of the determination in step (31) is No, it is determined whether the main power supply voltage Vin is lowered.
Then, when the determination result is Yes, the process returns to step (31).

(33) "Power-off of in-vehicle device 31" If the result of the determination in step (31) is Yes,
The supply of the power supply voltage to the vehicle-mounted device (car audio device) 31 is stopped. That is, the backup of the vehicle-mounted device 31 is stopped and the power-supply voltage from the vehicle-mounted battery 2 is not supplied. (34) “Ts> Tsmax2?” Next, it is determined whether or not the lowered state duration time Ts exceeds the reference Tsmax2 for the vehicle-mounted device (car navigation device) 32. As described above, the reference Tsmax2 is Tsmaxstart2 when the determination result of step (26) is Yes, and Tsmaxnormal2 when it is No.

(35) "Vin drop?" If the decision result in the step (34) is No, it is decided whether or not the main power supply voltage Vin is still down. Then, when the determination result is Yes, the step (3
Return to 4). (36) “Power supply stop of vehicle-mounted device 32” When the determination result of the above step (34) is Yes,
The supply of the power supply voltage to the vehicle-mounted device 32 is stopped. That is,
Backup of the vehicle-mounted device 32 is stopped and the main power supply voltage is not supplied.

(37) "Ts>Tsmax3?" Next, it is determined whether or not the lowered state duration time Ts exceeds the reference Tsmax3 for the vehicle-mounted device (security system) 33. As described above, this reference Tsmax3 is Tsmaxstart3 when the determination result of step (26) is Yes, and Tsmaxstart3 when it is No.
It becomes smaxnormal3.

(38) "Vin drop?" If the decision result in the step (37) is No, it is decided whether or not the main power supply voltage Vin is lowered.
Then, if the determination result is Yes, the process returns to step (37). (39) “Power supply stop of vehicle-mounted device 33” When the determination result of the above step (37) is Yes,
The supply of the power supply voltage to the vehicle-mounted device 33 is stopped. That is,
Backup of the vehicle-mounted device 33 is stopped and the main power supply voltage Vin is not supplied. afterwards,
The present flow shown in FIG. 4 is terminated, or the process proceeds to step (21) in FIG.

(40) "Switch to main power supply" When the result of the determination in step (32), (35) or (38) is No, the in-vehicle devices 31 to 3 are output through the outputs 1 to 3.
The power supply voltage to be supplied to 3 is the main power supply (vehicle battery 2)
Switch to the power supply voltage from. That is, the main power source is switched to the switched state. Then, after that, the process proceeds to step (1) of the flow shown in FIG. Then, after proceeding to the step (1), the flow shown in FIG. 2 is further advanced, and when the step (13) is completed, the procedure proceeds to the step (21) of FIG.

According to such a modification, the main power supply voltage Vin is measured, and when it rises, the timing of Ti is started from the start of the rise and the Ti when the power supply voltage Vin is lowered. Is greater than a preset Timax, and when the result of the determination is Yes, it is determined that the engine is started, and Tsma is used as a reference for comparison with the decrease time Ts.
xstart (Tsmaxstart1, 2, 3) is set, and when the determination result is No, it is determined that the engine has not been started and Tsmaxnormal (Tsmaxnormal1, 2, 3) is set.

After that, the clocking of the time Ts after the decrease of the power supply voltage Vin is started and the backup power supply voltage is sent from the outputs 1 to 3. Then, it is determined whether or not the time Ts is larger than Tsmaxstart or Tsmaxnormal. When the determination result is No, the drop is merely a momentary interruption, and the power supply voltage to each of the vehicle-mounted devices 31 to 33 is returned to the normal state in which it is supplied from the main power supply 2. FIG. 5A is a waveform diagram of the power supply voltage Vin and the power supply voltage output from one output in that case.

Then, the determination result of whether or not the time Ts is larger than Tsmaxstart or Tsmaxnormal is Yes.
When it occurs, it can be said that the deterioration of the in-vehicle device 3 related to the determination result is not a simple interruption, so the power supply to the in-vehicle device 3 is stopped. Such a flow is sequentially performed for the vehicle-mounted devices 31, 32, 33. Therefore,
The power supply to the vehicle-mounted device 3 in which the result recognized as an instantaneous interruption has occurred is stopped. That is, the output of the power supply voltage from the output that supplies the power supply voltage to the vehicle-mounted device 3 is stopped (the main power supply voltage Vin and the backup power supply voltage are not output). FIG. 5B is a waveform diagram of the power supply voltage Vin and the power supply voltage output from one output (for example, output 1) in that case.

In FIG. 5C, Ti> Timax, that is, not after the engine is started, and the power supply voltage Vin
Shows a case in which the time Ts is smaller than Tsmax even if there is a decrease, and it is determined that there is an instantaneous interruption, and the supply of the power supply voltage continues without being stopped. In the operation of FIGS. 3 and 4, the power supply from the output 1, 2 or 3 is stopped [Step (3
3), (36), (39)] is the premise of T.
s> Tsmaxstartn or Tsmaxnormaln (n = 1,
It may be performed after the shutdown waiting time Tw has elapsed after the determinations in 2 and 3).

This is because a shutdown waiting time Tw can be provided between the time when the power supply voltage from the vehicle-mounted battery is turned off and the time when the backup is stopped, and the time until the supply of the power supply voltage is stopped. This is because it is possible to perform processing that must be completed in order to turn off the power during the shutdown waiting time Tw. Then, as the shutdown standby time Tw, different values Tw1, Tw2, Tw3 can be set for each of the outputs 1, 2, 3. In this way, the in-vehicle device 31 connected to the outputs 1, 2, and 3
It is possible to deal with different shutdown waiting times required by ~ f.

FIGS. 6A to 6C and FIG. 7 are for explaining the second embodiment of the on-vehicle power supply control device of the present invention.
FIG. 6 (A) is a schematic system diagram of the electric system in the automobile, (B).
Is a configuration diagram of a power supply distribution unit that distributes the power supply voltage Vin from the vehicle-mounted battery and the power supply voltage from the backup battery,
(C) is a schematic configuration diagram of a power supply switching unit provided corresponding to each in-vehicle device, and FIG. 7 is a flowchart showing an operation in each power supply switching unit of the power supply control device. FIG. 6 of the present embodiment
An outline of the electric system in the vehicle shown in (A) is shown in FIG.
There are some commonalities with those shown in, but they differ in the following points.
The in-vehicle power supply control device 1b includes a power supply distribution unit 10b shown in FIG. 6B and power supply switching units 11b, 12b, 13b provided corresponding to the in-vehicle devices 31, 32, 33, respectively. Power distribution unit 1 that constitutes the power control device 1b
0b has a backup battery 8 as shown in FIG. 6 (B), and each of the power source switching units 11b, 12b, 13b.
A power supply voltage Vin from the vehicle-mounted battery 2 (a path for supplying the power supply is shown by a solid line) and a power supply voltage from the backup battery 8 (a path for supplying the power supply is shown by a broken line) are supplied to the vehicle.

Power source switching unit 1 constituting the power source control device 1b
As shown in FIG. 6C, 1b is an A / D converter 7a that detects the power supply voltage Vin from the vehicle-mounted battery 2,
A / for detecting the power supply voltage from the backup battery 8
Power supply voltage V from D converter 7b and vehicle-mounted battery 2
in and the power supply voltage from the backup battery 8,
The OR circuit 12 that outputs the higher power supply voltage,
It comprises an output voltage of the OR circuit 12 and a switch SW for switching it. The switch SW is controlled by the CPU 14 incorporated in the vehicle-mounted device 31 to be turned on or off. Reference numeral 15 is a ROM for storing a program executed by the CPU 14 in the vehicle-mounted device 31, and 16 is a RAM for temporarily storing the CPU 14 to execute the program.

Incidentally, the power source switching unit 12b and the power source switching unit 13b.
Also has the same configuration as the power source switching unit 11b shown in FIG. 6C, and the power source switching unit 12b is a CPU incorporated in the in-vehicle device 32.
The switch SW is controlled by 14, and the power source switching unit 13b
Is a switch S by the CPU 14 built in the in-vehicle device 33.
W is controlled. The power supply control device 1b includes a power switching unit 11 from the power supply distribution unit 10b to the on-vehicle devices 31 to 33.
Power supply voltage Vin from the vehicle-mounted battery 2 via b to 13b
The power source voltage from the backup battery 8 is sent out, and the power source switching units 11b to 13b independently control the switch SW. In these respects, the in-vehicle power supply control device
This is different from the on-vehicle power supply control device shown in FIG.

Next, the operation of one power supply switching section will be described with reference to FIG. It should be noted that this operation is independently and simultaneously performed in each of the power source switching units 11b to 13b. In normal times, the switch SW is held in the ON state, and thus the output of the OR circuit 12 is supplied to the vehicle-mounted device, for example 31, as the power supply voltage. (51) "Voltage Vin drop?" First, the main power supply voltage Vin is detected (the detection output of the A / D converter 7a is taken in), and it is determined whether or not the detected power supply voltage Vin has dropped. Specifically, it is determined whether or not there is a drop equal to or higher than the drop allowance fine voltage ΔVin set as the maximum voltage allowed to drop.
If the determination result is No, that is, the main power supply voltage Vi
If n does not decrease, this determination is repeated until a determination result of Yes is obtained.

(52) "Activation of Ts Timer" If the result of the determination in step (51) is Yes, the Ts timer for measuring the duration Ts of the low state of the power supply voltage Vin is immediately activated. That is, the Ts timer starts counting the lowered state duration time Ts.

(53) "Ts>Tsmaxn?" Next, it is determined whether or not the lowered state duration time Ts is longer than the instantaneous interruption maximum time Tsmaxn of the vehicle-mounted device 3. As described above, the maximum instantaneous interruption time Tsmax is the time for determining an instantaneous interruption when it is shorter than that as a reference for determining whether or not there is an instantaneous interruption. ,
If it is longer than this, it is recognized as a time that can be recognized as a stop of the power supply voltage from the vehicle-mounted battery 2 instead of an instantaneous interruption. It should be noted that this instantaneous interruption maximum time Tsmax is the same as that of the first embodiment in that it is set to a different value depending on the type of the vehicle-mounted device, and Tsmaxn is Tsmax1 for the vehicle-mounted device 31,
The in-vehicle device 32 is Tsmax2, and the in-vehicle device 33 is Tsmax3.

(54) "Vin drop?" If the decision result in the step (53) is No, it is decided whether or not the power supply voltage Vin is lowered. This is nothing but the determination as to whether or not the power supply voltage continues to decrease, and when the determination result is Yes, the above step (5) is performed.
Return to 3). Conversely, if the determination result is No, that is,
Since the power supply voltage Vin has returned to the original value, the above power supply voltage V
It can be said that the decrease of in is due to the instantaneous interruption. Therefore,
The process returns to step (51) without turning off the switch SW. (55) “The in-vehicle device 3n stops after Twn” When the determination result of the step (53) is Yes, the supply of the power supply voltage to the in-vehicle device 3n is stopped after the shutdown waiting time Twn of the in-vehicle device 3 has elapsed. In particular,
The switch SW is turned off. As a result, the in-vehicle device 3
The operation of n is stopped.

According to such an embodiment, even if the power supply voltage Vin of the vehicle-mounted battery 2 (main power supply) drops,
Since the OR circuit 12 can output the power supply voltage from the backup battery 8, backup can be performed when the voltage drops. Therefore, even if there is a momentary interruption, backup can be performed by the backup battery 8. FIG. 8B is a waveform diagram showing the main power supply voltage Vin and the backup power supply voltage when the instantaneous interruption is backed up.

The time T during which the lowered state continues
When s exceeds Tsmaxn of the vehicle-mounted device 3n, it is considered from the standpoint of the vehicle-mounted device 3n that the power supply is stopped, and the switch SW of the OR circuit 12 is turned off after the lapse of the shutdown waiting time Twn. Therefore, when the power supply is stopped, the stop can be confirmed, and after the shutdown standby time Twn corresponding to the vehicle-mounted device 3n has elapsed, the switch SW of the OR circuit 12 can be turned off to stop the backup. FIG. 8A is a waveform diagram showing the main power supply voltage Vin and the power supply voltage from the backup battery (backup power supply) 8 in such a case.

FIG. 9 is a flow chart for explaining the operation of one power source switching unit, for example, 11b, which is a modification of the embodiment 1b shown in FIGS. The present modification backs up even momentary interruptions caused by a drop in the power supply voltage Vin that is inevitably generated at engine start-up, and when an original power supply stop occurs, the supply of the power supply voltage is stopped accordingly. There is a difference from the flowchart shown in FIG. That is, the decrease of the main power supply voltage Vin is due to the stop of the supply of the power supply voltage Vin and the momentary interruption which necessarily occurs at the time of starting the engine. When the supply of the power supply voltage Vin is stopped, the supply of the power supply voltage Vin is stopped. While it is necessary to stop the engine, it is necessary to back up the momentary interruption that occurs when the engine is started and to supply the original power supply voltage Vin after the momentary interruption. It is to meet that need.

The circuit configuration of this modification is the same as that of the embodiment 1b shown in FIGS. 6 and 7, and only the operation program is different. Therefore, illustration and description of the circuit configuration are omitted. To do. Further, the operation of each power source switching unit is performed independently of each other, but since they are basically the same, only the operation of one power source switching unit will be described with reference to FIG. In the initial state, the switch SW of the power source switching unit maintains the normal state, that is, the on state.

(61) "Vin rise?" After starting the engine, first, the main power supply voltage Vin is detected (the detection output of the A / D converter 7a is taken in), and it is determined whether or not the power supply voltage Vin is rising. To do. In the operation of this modified example, first, it is indispensable to detect the rise of the main power supply voltage Vin, and therefore, first, it is detected whether or not the power supply voltage Vin is rising. When the determination result is No, the determination is repeated until the determination result of Yes is obtained.

(62) "Ti timer activation" If the result of the determination in step (61) is Yes, that is, if the power supply voltage Vin rises, the power supply voltage V
By starting the Ti timer that measures the high duration time Ti after engine start, which is the elapsed time after the rise of in, the timing of high continuation Ti after engine start is started. (63) “Vin drop?” Next, it is determined whether the power supply voltage Vin has dropped. When the determination result is No, the determination is repeated until the determination result of Yes is obtained.

(64) "Stop Ti Timer" When the result of the determination in step (63) is Yes, the timing of the high continuation time Ti after engine start by the Ti timer is stopped. (65) “Ti <Timax?” The high continuation time Ti after starting the engine and the high continuation maximum time after starting Timax are compared to determine whether or not the Ti is smaller than Timax. High continuation maximum time at startup Tima
x is the time Ti until the power supply voltage Vin after starting rises after the power supply voltage Vin after starting rises, which is a reference for determining that the engine has been started when the time is shorter than that in order to determine whether or not the engine has been started. That is as described above. Therefore, when the high duration time Ti after starting is shorter than the high duration maximum time Timax after starting, it is determined that the engine has been started, and the high duration time Ti after starting is the high duration maximum time after starting Tima.
If it is longer than x, it is determined that it is not after the engine is started.

(66) "Setting Tsmaxstart" If the determination result of the step (65) is Yes, that is, if Ti <Timax, the engine is starting, and the power supply voltage Vin is lowered after the engine is started. Tsmaxstartn is used as a comparison reference Tsmax for judging whether the power supply is stopped or an instantaneous interruption occurs for the running time Ts.
To set. Tsmaxstartn is Tsmaxstart1 in the case of in-vehicle device 31 (car audio device), in-vehicle device 32
(Car navigation device) Tsmaxstart2, In-vehicle device 33 (security system) Tsmaxs
It becomes tart3.

(67) "Tsmax normal setting" If the determination result of the step (65) is No, that is, if Ti> Timax, it means that the engine is not starting, and in this case, the power supply voltage Vin is Tsmaxno as a comparison reference Tsmax in the comparison for determining whether there is an instantaneous interruption or a power supply stop for the decreasing time Ts
Set rmaln. Tsmaxnormaln is the in-vehicle device 31
(Car audio device) Tsmaxnormal1, in-vehicle device 32 (car navigation device) Tsmaxnor
In the case of mal2 and in-vehicle device 33 (security system), Tsmaxnormal3 is set. In this way, the in-vehicle device 3
The reason why the values of Tsmaxstart and Tsmaxnormal are changed according to 1 to 33 is to enable to cope with the difference in the characteristics of the in-vehicle devices 31 to 33 with respect to the instantaneous interruption.

(68) "Activation of Ts timer" Next, the lowering state duration time Ts of the main power supply voltage Vin
Start the Ts timer that keeps time. That is, the timing of Ts is started. (69) “Ts> Tsmaxn?” Then, the lowered state duration Ts is the in-vehicle device 3 concerned.
Step (66) for n (when the engine is started: When the determination result of Yes is obtained in step (65)) or Step (67) [In the normal case: When the determination result of No is obtained in step (65)] When obtained] T
The value set as smax (Tsmaxstartn or Tsmax
It is determined whether the normal n) is exceeded.

(70) "Vin drop?" If the decision result in the step (69) is No, it is decided whether or not the main power supply voltage Vin is lowered.
Then, if the determination result is Yes, the process returns to step (69). When the determination result is No, the process proceeds to step (51) in the flow shown in FIG. (71) “Stop in-vehicle device after Twn” If the determination result of the above step (69) is Yes,
Supplying a power supply voltage to the in-vehicle device 3n
It stops after the elapse of the shutdown waiting time Twn for n. Specifically, the stop is performed by turning off the switch SW of the power supply switching unit.

According to the on-vehicle power supply control device 1b, the main power supply voltage Vin is measured, and if it rises, the timing of Ti is started from the start of the rise and the power supply voltage Vin is lowered. It is determined whether or not its Ti is larger than a preset Timax. If Yes, it is determined that the engine is started, and Tsmaxstartn (Tsmaxstart1, 2, 3) is set as a reference for comparison with the decrease time Ts. Conversely, when the determination is No, it is determined that the engine has not been started, and Tsmaxnormaln (Tsmaxnormal1, 2,
3) is set. After that, the time counting of the time Ts after the power supply voltage Vin is lowered is started. And that time Ts
Is greater than Tsmaxstartn or Tsmaxnormaln. When the determination result is No, the decrease is merely an instantaneous interruption and the switch SW is not turned off. FIG. 10A is a waveform diagram of the power supply voltage Vin and the power supply voltage output from the power supply switching unit corresponding to the vehicle-mounted device 3n in that case.

Then, the judgment result of whether or not the time Ts is larger than Tsmaxstartn or Tsmaxnormaln is Y.
When es occurs, it can be said that the deterioration of the vehicle-mounted device 3n according to the determination result is not a simple interruption, so the supply of power to the vehicle-mounted device 3n is stopped. Specifically, the switch SW of the power source switching unit is turned off. Figure 10
(B) is a waveform diagram of the power supply voltage Vin and the power supply voltage output from one output in that case. Incidentally, FIG.
In (C), Ti> Timax, that is, not after the engine is started, and even if the power supply voltage Vin decreases, the time Ts is smaller than Tsmax, it is determined that there is an instantaneous interruption, and the supply of the power supply voltage is stopped. No, it shows the case of continuing.

11 (A), (B) and FIG. 12 are for explaining the third embodiment 1c of the on-vehicle power supply control device of the present invention, and FIG. 11 (A) is a schematic diagram of the electric system in the automobile. A system diagram, (B) is a schematic block diagram of a vehicle-mounted power supply control device, and FIG. 12 is a flowchart showing an operation of the vehicle-mounted power supply control device.
First, the electric system in the automobile will be described. The outline of the electric system is as an in-vehicle power supply control device 1c
1 is different from that shown in FIG. 1A, but the other points are common.

Next, the in-vehicle power supply control device 1c will be described with reference to FIG. 8 is a backup battery, 7a is an A / D converter that detects the main power supply voltage Vin, 7b is an A / D converter that detects the power supply voltage from the backup battery 8, and 12 _{1 to} 12 ₃ are compatible with the in-vehicle devices 31 to 32. The OR circuit provided in this way receives the power supply voltage Vin from the vehicle-mounted battery 2 and the power supply voltage from the backup battery 8, and outputs the higher power supply voltage.

SW1 to SW3 are the OR circuits 12₁~ 1
Two₃The switch provided for each
Between the output side of the circuit 12 and the corresponding in-vehicle device 3
The power supply voltage is turned on and off by intervening. That is,
SW1 is an OR circuit 12 ₁Output and in-vehicle equipment
(Car audio device) 31 and switch
SW2 is an OR circuit 12₂Output and in-vehicle equipment (car
(Navigation device) 32 and a switch S
W3 is an OR circuit 12₃Output and in-vehicle equipment (security
(Rightity system) 33. And each
Each of the switches SW1 to SW3 is a CPU described below.
Controlled by (4)

Reference numeral 4 controls the CPU (central processing unit) and the in-vehicle power supply control device 1c. A ROM (Read Only Memory) 5 stores programs executed by the CPU 4. Reference numeral 6 denotes a RAM that performs temporary storage necessary when the CPU 4 executes the program stored in the ROM 5. The CPU 4, the ROM 5, and the RAM 6 are included in the in-vehicle power supply control device 1c, and are different from each other in the in-vehicle devices 31 to 32.
It is different from the CPU 14, ROM 15, and RAM 16 shown in FIG.

The operation will be described below with reference to FIG. In this embodiment, the switches SW1 to SW3 are normally operated.
Is turned on, and each OR circuit 12 _{1 to} 12 ₃
From the main power supply voltage Vin or the output power supply voltage of the backup battery 8, whichever is higher. This state will be referred to as the normal state of this embodiment.

(81) "Voltage Vin drop?" First, the main power supply voltage Vin is detected (the detection output of the A / D converter 7a is taken in), and it is determined whether or not the detected power supply voltage Vin has dropped. . Specifically, it is determined whether or not there is a drop equal to or higher than the drop allowance fine voltage ΔVin set as the maximum voltage allowed to drop.
If the determination result is No, that is, the main power supply voltage Vi
If n does not decrease, this determination is repeated until a determination result of Yes is obtained.

(82) "Activation of Ts Timer" If the result of the determination in step (82) is Yes, the Ts timer for measuring the lowering state duration Ts of the power supply voltage Vin is immediately activated. That is, the Ts timer starts counting the lowered state duration time Ts. As described above, in this embodiment, backup is automatically performed without providing a special step for backup.

(83) “Ts> Tsmax1?” Then, the maximum state time Ts of the vehicle-mounted device 31 (car audio device) connected to the output 1 with the lowered state duration Ts is Ts.
It is determined whether it is longer than max1. Maximum interruption time Tsmax
Is the time to be judged as a momentary interruption when it is shorter than that as a criterion for determining whether or not it is a momentary interruption. Therefore, if it is shorter than this, it is recognized as a momentary interruption, and if it is longer than this, it is not a momentary interruption and As described above, it is recognized that the power supply voltage from the battery is stopped. Also in the present embodiment, the maximum instantaneous interruption time Tsmax is set to a different value depending on the type of the in-vehicle device, Tsmax1 for the in-vehicle device 31, Tsmax2 for the in-vehicle device 32, and Ts for the in-vehicle device 33.
smax3 and different values (in this example, Tsmax1 <T
smax2 <Tsmax3) is set.

(84) "Vin drop?" If the decision result in the step (83) is No, it is decided whether or not the power supply voltage Vin is lowered. This is nothing but the determination as to whether or not the power supply voltage continues to decrease, and when the determination result is Yes, the above step (8) is performed.
Returning to step 3), if the determination result is No, the process returns to step (81). (85) “Stop the in-vehicle device 31 after Tw1” If the determination result of the above step (84) is Yes, it is not recognized as a momentary interruption from the standpoint of the in-vehicle device 31, so that the in-vehicle device after the shutdown waiting time Tw1 has elapsed. The supply of the power supply voltage to 31 is stopped. Specifically, the switch S
Turn off W1.

(86) "Ts>Tsmax2?" Whether the lowered state duration time Ts is longer than the instantaneous interruption maximum time Tsmax2 of the vehicle-mounted device 32 (car navigation device) connected to the output 1 after the vehicle-mounted device 31 is stopped. To determine. (87) “Vin lowered?” When the result of the determination in step (86) is No, it is determined whether the power supply voltage Vin has dropped. This is nothing but the determination as to whether or not the power supply voltage continues to decrease, and when the determination result is Yes, the above step (8) is performed.
Returning to 6), if the determination result is No, the procedure returns to step (81).

(88) "Stop the in-vehicle device 32 after Tw2" If the determination result of the above step (86) is Yes, it is not recognized as a momentary interruption from the standpoint of the in-vehicle device 32. Therefore, after the shutdown waiting time Tw2 has elapsed. The supply of the power supply voltage to the vehicle-mounted device 32 is stopped. Specifically, the switch S
Turn off W2. (89) “Ts> Tsmax3?” After the vehicle-mounted device 32 is stopped, it is determined whether the lowered state duration time Ts is longer than the instantaneous interruption maximum time Tsmax3 of the vehicle-mounted device 33 (security system) connected to the output 3. .

(90) "Vin drop?" If the decision result in the step (89) is No, it is decided whether or not the power supply voltage Vin is lowered. This is nothing but the determination as to whether or not the power supply voltage continues to decrease, and when the determination result is Yes, the above step (8) is performed.
Returning to 9), if the determination result is No, the procedure returns to step (81). (91) “Stop the in-vehicle device 33 after Tw3” When the determination result of the above step (89) is Yes, since it is not recognized as a momentary interruption from the standpoint of the in-vehicle device 33, the in-vehicle device after the shutdown waiting time Tw3 has elapsed. The supply of the power supply voltage to 33 is stopped. Specifically, the switch S
Turn off W3. Then, this flow ends. Alternatively, the process proceeds to step (101) of the flow shown in FIG. 13, which will be described later.

According to such an embodiment, even if the power source voltage Vin of the vehicle-mounted battery 2 (main power source) drops,
Since the OR circuit 12 can output the power supply voltage from the backup battery 8, backup can be performed when the voltage drops. Therefore, even if there is a momentary interruption, it is possible to back up with the backup battery 8. It should be noted that the main power supply voltage Vin when the instantaneous interruption is backed up and the power supply voltage V of the on-vehicle battery (main power supply) 2 output from the on-vehicle power supply control device 1b.
In and the waveform of the power supply voltage from the backup battery (backup power supply) 8 output from the vehicle-mounted power supply control device 1b are the same as those shown in FIG.

The time T during which the lowered state continues
When s exceeds Tsmax1, the in-vehicle device (car audio device) 31 to which the power supply voltage is supplied from the output 1
From the standpoint of the above, it is considered that the power supply is stopped, and after it is considered that the shutdown standby time Tw1 has elapsed, the switch S of the OR circuit 12
Turn off W1. Furthermore, when Tsmax2 is exceeded,
From the standpoint of the vehicle-mounted device (car navigation device) 32 that receives the power supply voltage from the output 2, it is considered that the power supply is stopped, and after that, after the shutdown standby time Tw2 has elapsed,
The switch SW2 of the OR circuit 12 is turned off.

Further, when Tsmax3 is exceeded, from the standpoint of the in-vehicle device (security system) 33 which is supplied with the power supply voltage from the output 3, it is considered that the power supply is stopped, and the switch SW3 of the OR circuit 12 is turned off. Therefore, when the power supply is stopped, the stop can be confirmed, and after the shutdown waiting time Tw has elapsed, the switch SW of the OR circuit 12 can be turned off to stop the backup. Then, in such a case, the main power supply voltage Vin and the in-vehicle battery (main power supply) output from the in-vehicle power supply control device 1b
The waveforms of the power supply voltage Vin of No. 2 and the power supply voltage from the backup battery (binding up power supply) 8 output from the in-vehicle power supply control device 1b are the same as those shown in FIG.

FIG. 13 shows the first embodiment shown in FIGS. 11 and 12.
It is a flow chart explaining operation of a modification of c. This modification is intended to back up a momentary interruption due to a drop in the power supply voltage Vin that is inevitably generated at the time of starting the engine, and to stop the supply of the power supply voltage accompanying the original power supply stop. In that respect, it differs from the flowchart shown in FIG. It is necessary to back up the momentary interruption that occurs when the engine is started and to supply the original power supply voltage Vin after the momentary interruption, and this modification is to meet the need.

The circuit configuration of this modification is shown in FIGS.
The circuit configuration is the same as that of the embodiment 1c shown in FIG. 1 and only the operation program is different, and therefore the illustration and description of the circuit configuration are omitted. The operation of the modified example will be described below with reference to FIG. The switches SW1 to SW3 are kept in the normal state and the on state in the initial state. (101) "Vin rise?"

After the engine is started, first, the main power supply voltage V
in is detected (capture of the detection output of the A / D converter 7a), and it is determined whether or not the power supply voltage Vin has risen. In the operation of this modification, first, it is essential to detect the rise of the main power supply voltage Vin, and therefore, first, it is detected whether or not the power supply voltage Vin is rising. When the determination result is No, the determination is repeated until the determination result of Yes is obtained.

(102) "Ti timer activation" When the result of the determination in the above step (101) is Yes, that is, when the power supply voltage Vin rises, immediately after the power supply voltage Vin has risen, which is the elapsed time after the engine starts, By starting the Ti timer that measures the duration Ti, the timing of the high continuation Ti is started after the engine is started. (103) “Vin lowered?” Next, it is determined whether the power supply voltage Vin has dropped. When the determination result is No, the determination is repeated until the determination result of Yes is obtained.

(104) "Ti Timer Stop" When the result of the determination in the above step (103) is Yes, the high duration time Ti after engine start by the Ti timer is
Stop timing. (105) “Ti <Timax?” The high continuation time Ti after starting the engine is compared with the high continuation maximum time Timax after starting the engine to determine whether or not the Ti is smaller than Timax. High continuation maximum time at startup Tima
x is the time Ti until the power supply voltage Vin after starting rises after the power supply voltage Vin after starting rises, which is a reference for determining that the engine has been started when the time is shorter than that in order to determine whether or not the engine has been started. That is as described above.

(106) "Tsmaxstart (1, 2, 3)
“Setting” If the determination result of the above step (105) is Yes, that is, if Ti <Timax, the engine is starting, and after this engine starting, the power supply voltage Vin is decreased for a short time Ts. As a comparison reference Tsmax for determining whether to disconnect or stop the power supply, Tsmaxstart1 for the in-vehicle device 31 and Tsmax for the in-vehicle device 32 are used.
smaxstart2, Tsmaxstart for in-vehicle device 33
Set 3. (107) “Tsmax normal setting” If the determination result of the step (105) is No, that is, if Ti> Timax, it means that the engine is not started, and in this case, the power supply voltage Vin decreases. As the comparison reference Tsmax in the comparison for determining whether there is a momentary interruption or a power stop for the time Ts, Tsmaxnormal1 is set for the in-vehicle device 31, Tsmaxnormal2 is set for the in-vehicle device 32, and Tsmaxnormal3 is set for the in-vehicle device 33.

(108) "Ts Timer Start" Next, the lowering state duration time Ts of the main power supply voltage Vin.
Start the Ts timer that keeps time. That is, the timing of Ts is started. (109) “Ts> Tsmax1?” Then, the lowered state duration time Ts is the step (106) of the in-vehicle device 31 [when the engine is started:
The value (Tsmaxstart1) set as Tsmax1 in step (105) when the determination result is Yes] or in step (107) [in the normal case: when the determination result is No in step (105)] Or T
It is determined whether smaxnormal1) is exceeded.

(110) "Vin drop?" If the judgment result of the above step (109) is No,
It is determined whether the main power supply voltage Vin has dropped. If the determination result is Yes, step (10
Return to 9). Further, when the determination result is No, FIG.
Proceed to step (81) in the flow shown in. (111) “Stop the in-vehicle device 31 after Tw1” If the determination result of the step (109) is Yes, supply of the power supply voltage to the in-vehicle device 31 is stopped after the shutdown waiting time Tw1 of the in-vehicle device 3 has elapsed. To do. Specifically, the stop is the switch SW of the power supply switching unit.
This is done by turning off 1.

(112) "Ts>Tsmax2?" Then, the lowered state duration time Ts is the same as the step (106) [in the case of engine starting:
A value (Tsmaxstart2) set as Tsmax2 in the case where the determination result of Step (105) is Yes] or in the step (107) [in the normal case: when the determination result of No is obtained in Step (105)] Or T
It is determined whether smaxnormal2) is exceeded. (113) “Vin drop?” When the determination result of the step (112) is No,
It is determined whether the main power supply voltage Vin has dropped. If the determination result is Yes, step (11
Return to 2). Further, when the determination result is No, FIG.
Proceed to step (81) in the flow shown in.

(114) "Stop the in-vehicle device 32 after Tw2" When the result of the determination in the above step (112) is Yes, the power source voltage is supplied to the in-vehicle device 32.
Is stopped after the elapse of the shutdown waiting time Tw2. Specifically, the stop is the switch SW of the power supply switching unit.
This is done by turning off 2. (115) “Ts> Tsmax3?” Then, the lowered state duration time Ts is the step (106) of the in-vehicle device 33 [when the engine is started:
The value set as Tsmax3 (Tsmaxstart3) when the determination result of Yes is obtained in step (105)] or in the case of step (107) [in the normal case: when the determination result of No is obtained in step (105)] Or T
It is determined whether smaxnormal3) is exceeded.

(116) "Vin drop?" If the determination result of the above step (115) is No,
It is determined whether the main power supply voltage Vin has dropped. If the determination result is Yes, step (11
Return to 5). Further, when the determination result is No, FIG.
Proceed to step (81) in the flow shown in. (117) “Stop the in-vehicle device 33 after Tw3” When the determination result of the step (112) is Yes, the power supply voltage is supplied to the in-vehicle device 33.
The shutdown is stopped after the elapse of the shutdown waiting time Tw3. Specifically, the stop is the switch SW of the power supply switching unit.
This is done by turning off 2. Then, this flow is completed or returns to step (101).

In such a modified example, the main power supply voltage Vin is measured, and when it rises, the timing of Ti is started from the start of the rise, and the Ti when the power supply voltage Vin drops is measured. It is determined whether or not it is larger than a preset Timax, and if Yes, it is determined that the engine has started, and Tsmaxstart (Tsmaxstart1, 2, 3) is set for each in-vehicle device 3 as a reference for comparison with the decrease time Ts. On the contrary, when the determination is No, it is determined that the engine has not been started and Tsmaxnormal corresponding to each in-vehicle device 3.
(Tsmaxnormal1, 2, 3) is set. After that, the time counting of the time Ts after the power supply voltage Vin is lowered is started. Then, the time Ts is the above Tsmaxstart or T
It is determined whether it is larger than smaxnormal. When the determination result is No, the drop is merely a momentary interruption, and the power supply voltage to each of the vehicle-mounted devices 31 to 33 is returned to the normal state in which it is supplied from the main power supply 2.

Then, the determination result of whether or not the time Ts is larger than Tsmaxstart or Tsmaxnormal is Yes.
When it occurs, it can be said that the deterioration of the in-vehicle device 3 related to the determination result is not a simple interruption, so the power supply to the in-vehicle device 3 is stopped. Such a flow is sequentially performed for the vehicle-mounted devices 31, 32, 33. Therefore,
The power supply to the vehicle-mounted device 3 in which the result recognized as an instantaneous interruption has occurred is stopped. That is, the transmission of the power supply voltage from the output that supplies the power supply voltage to the vehicle-mounted device 3 is stopped (the main power supply voltage Vin and the output voltage of the backup battery are not output).

When Ts <Tsmax and the power supply voltage Vin drops momentarily, the waveforms of the power supply voltage Vin and the power supply voltage output from the power supply switching unit corresponding to the on-vehicle device 3 are shown in FIG. ), And the result of the determination as to whether or not the time Ts is greater than Tsmaxstartn or Tsmaxnormaln is Yes, and the power supply voltage Vin and the power supply output from one output when it can be said that it is not a simple interruption The waveform of the voltage is as shown in FIG. 10 (B), and Ti> Timax, that is, not after the engine is started, and even if the power supply voltage Vin decreases, the time Ts is smaller than Tsmax, and the interruption occurs. When the determination is made and the supply of the power supply voltage is not stopped but continued, the waveform is as shown in FIG.

FIGS. 14A and 14B and FIG. 15 are for explaining the third embodiment of the on-vehicle power supply control device of the present invention, and FIG. 14A is a schematic diagram of the electric system in the automobile. A system diagram, (B) is a schematic block diagram of a vehicle-mounted power supply control device, and FIG. 15 is a flowchart showing an operation of the vehicle-mounted power supply control device.
The outline of the electric system in the automobile of this embodiment shown in FIG. 14 (A) is common to that shown in FIG. 1 (A),
A line for supplying the power supply voltage Vin from the vehicle-mounted battery (main power supply) 2 or the power supply voltage from the backup battery (backup power supply) 8 to the vehicle-mounted devices 31 to 33 from the vehicle-mounted power supply control device 1d. The difference is that a control system for transmitting a control signal for turning the power on and off is provided, but the other points are common, and since the common points have already been described, detailed description thereof will be omitted. .

In-vehicle power supply control device 1d shown in FIG. 14B.
Is a CPU 4, a ROM 5, a RAM 6, an A / D converter 7 for detecting a power supply voltage Vin, and a backup battery 8.
1B, the vehicle-mounted power supply control device 1a shown in FIG.
Common with. However, the in-vehicle power supply control device 1d differs from the in-vehicle power supply control device 1a in that it has the power supply controller 17 and the control circuit 18. First, the power supply controller (power supply switching circuit) 17 determines the power supply voltage Vi from the in-vehicle battery 2.
n and the output voltage from the backup battery 8,
The main power supply voltage Vin or the output voltage of the backup battery 8 is sent to the output 1, 2 or 3 under the control of the control signal from the CPU 4. Which of the outputs 1 to 3 is used to supply the power supply voltage, and when supplied, which of the main power supply voltage Vin and the output voltage of the backup battery 8 is used as the power supply voltage is CP.
Follow the control signal from U4.

The control circuit 18 is controlled by the CPU 4,
A stop signal for turning off the power is sent to each of the vehicle-mounted devices 31-33, and a start signal for turning on the power is sent to each of the vehicle-mounted devices 31-33 in the off state. In-vehicle equipment 31
Upon receipt of a stop signal in the operating state, each of ~ 33 immediately prepares to turn off its own power supply, and does not cause a failure or other trouble even if the supply of the power supply voltage is stopped before the self-shutdown standby time Tw elapses. A state can be formed. Further, it operates so as to receive a start signal in a stopped state upon receiving a stop signal.

The operation of this embodiment will be described below with reference to FIG. In the present embodiment, the in-vehicle power supply control device 1c
Normally, the power supply controller 17 has the in-vehicle devices 31 to 31.
It is assumed that the main power supply voltage Vin is sent to 33 and the control circuit 18 is in a state of not sending a stop signal to the vehicle-mounted devices 31 to 33. Then, this state is referred to as a normal state. (121) “Vin drop?” ”First, the main power supply voltage Vin is detected (the detection output of the A / D converter 7 is taken in), and the detected power supply voltage V is detected.
It is determined whether or not in has decreased. Specifically, it is determined whether or not there is a drop equal to or higher than the drop allowance fine voltage ΔVin set as the maximum voltage allowed to drop. If the determination result is No, that is, the main power supply voltage Vin
If no decrease occurs, this determination is repeated until a determination result of Yes is obtained.

(122) "Activation of Ts Timer" When the result of the determination in step (121) is Yes, the Ts timer for measuring the lowering state duration Ts of the power supply voltage Vin is immediately activated. That is, the Ts timer starts counting the lowered state duration time Ts. (123) “Ts> Tsmax1?” Next, it is determined whether or not the lowered state duration time Ts is longer than the instantaneous interruption maximum time Tsmax1 for the vehicle-mounted device 31 (car audio device) connected to the output 1. The instantaneous interruption maximum time Tsmax is a time for determining an instantaneous interruption when it is shorter than that as a reference for determining whether or not an instantaneous interruption occurs. Therefore, if it is shorter than this, it is recognized as an instantaneous interruption, and if it is longer than this. It is certified as a time that can be recognized as a stop of the power supply voltage from the onboard battery rather than a momentary interruption.

The instantaneous interruption maximum time Tsmax of the vehicle-mounted device (car audio device) 31 connected to the output 1 is set to Tsmax.
1, the maximum instantaneous interruption time Tsmax of the vehicle-mounted device (car navigation device) 32 connected to the output 2 is Tsmax2, the output 3
(Security system) Maximum interruption time Tsmax of 33
Is Tsmax3. (124) “Vin decreased?” When the result of the determination in step (123) is No, it is determined whether the power supply voltage Vin has decreased. this is,
It is nothing but the determination as to whether or not the power supply voltage reduction state continues, and if the determination result is Yes, then the above step (1)
23), and if No, returns to step (121).

(125) "Send Stop Signal to In-Vehicle Equipment 31" When the result of the determination in step (123) is Yes, the stop signal for supplying the power supply voltage is sent to the in-vehicle apparatus 31. When the vehicle-mounted device 31 receives the stop signal, the vehicle-mounted device 31 forms a state in which no problem occurs even if the supply of the power supply voltage is stopped. A shutdown waiting time Tw1 is required to form this state. (126) “Stop the in-vehicle device 31 after Tw1” After the stop signal is transmitted in step (125), the shutdown waiting time Tw1 of the in-vehicle device 31 is measured, and after the time Tw1 has elapsed, the power supply controller 17 causes the in-vehicle device 3 to proceed.
The supply of the power supply voltage to 1 is stopped.

(127) "Ts>Tsmax2?" Next, it is determined whether or not the lowered state duration time Ts is longer than the instantaneous interruption maximum time Tsmax2 for the vehicle-mounted device 32 (car navigation device) connected to the output 2. (128) “Vin drop?” When the result of the determination in step (127) is No, it is determined whether the power supply voltage Vin has dropped. If the determination result is Yes, the process returns to the above step (127),
In No, it returns to step (121).

(129) "Send stop signal to in-vehicle device 32" If the determination result in step (127) is Yes, the stop signal is transmitted to the in-vehicle device 32. When the vehicle-mounted device 32 receives the stop signal, the vehicle-mounted device 32 forms a state in which no problem occurs even if the supply of the power supply voltage is stopped. A shutdown waiting time Tw2 is required to form this state. (130) “Stop in-vehicle device 32 after Tw2” After transmitting the stop signal in step (125), the shutdown waiting time Tw2 of the in-vehicle device 32 is measured, and after the time Tw2 has elapsed, the power supply controller 17 causes the in-vehicle device 3 to proceed.
The supply of the power supply voltage to 2 is stopped.

(131) "Ts>Tsmax3?" Next, it is determined whether or not the lowered state duration time Ts is longer than the maximum interruption time Tsmax3 of the vehicle-mounted device 33 (security system) connected to the output 3. (132) “Vin lowered?” When the result of the determination in step (127) is No, it is determined whether the power supply voltage Vin is lowered. If the determination result is Yes, the process returns to the above step (127),
In No, it returns to step (121).

(133) "Send Stop Signal to In-Vehicle Equipment 33" If the determination result in step (131) is Yes, the stop signal is sent to the in-vehicle apparatus 33. When the vehicle-mounted device 33 receives the stop signal, it forms a state in which no problem occurs even if the supply of the power supply voltage is stopped. A shutdown waiting time Tw3 is required to form this state. (134) “Stop the in-vehicle device 33 after Tw3” After the stop signal is transmitted in step (133), the shutdown standby time Tw3 of the in-vehicle device 33 is measured, and after the time Tw2 has elapsed, the power supply controller 17 causes the in-vehicle device 3 to stop.
The supply of the power supply voltage to 3 is stopped. After that, this flow is ended, or the flow proceeds to the flow shown in FIG. 17 described later.

According to such a vehicle-mounted power supply control device 1d, the main power supply voltage Vin detected by the A / D converter 7 which is the power supply voltage detecting means is detected, and it is judged whether or not the main power supply voltage Vin is decreased, and there is no decrease. In this case, the normal state is maintained, and when there is a drop in the power supply voltage Vin, the counting of the lowered state duration Ts, which is the elapsed time of the lowered state, is started, and the power supply controller 17 causes the backup battery 8 The power supply voltage from can be supplied. Therefore, even if a temporary drop in the main power supply voltage Vin occurs, it is possible to prevent the in-vehicle devices 31 to 33 from being damaged and causing a malfunction. FIG. 16B is a waveform diagram showing the power supply voltage Vin from the vehicle-mounted battery 2, the power supply voltage from the power supply controller 17, and the stop signal at that time.

If the drop time Ts of the power source voltage Vin exceeds the maximum interruption time Tsmax, it cannot be said that the interruption is instantaneous. Therefore, the control circuit 18 transmits a stop signal to the in-vehicle device 3, and then the shutdown waiting time. When Tw elapses, that is, when the in-vehicle device 3 is ready to stop the supply of the power supply voltage, the supply of the power supply voltage from the power supply controller 17 can be stopped, and the supply of the power supply voltage is stopped in the vehicle. It is possible to stop the supply of the power supply voltage so as not to cause a trouble such as a failure in the device 3. FIG. 16A shows a power supply voltage Vin from the vehicle-mounted battery 2 in such a case,
6 is a waveform diagram showing a power supply voltage and a stop signal from the power supply controller 17. FIG. And such a thing is sequentially performed about each vehicle-mounted apparatus 31, 32, 33.

FIG. 17 is a flow chart for explaining the operation of the modification of the embodiment 1d shown in FIGS. 14 and 15. 18A to 18C are waveform diagrams showing the power supply voltage Vin that is the output of the main power supply (vehicle-mounted battery 2) and the power supply voltage that is output from the vehicle-mounted power supply control device 1d. ) Is the high continuation time Ti after engine start described later <the maximum high continuation time after engine start described later,
In the case of Ts <Tsmax, FIG. 18B shows that the high continuation time Ti after the engine start <the high continuation maximum time T after the engine start
In the case of imax, Ts> Tsmax, FIG. 18C shows the case of high continuation time Ti after engine start> high continuation maximum time Timax after engine start, Ts <Tsmax.

The operation of this modification will be described with reference to FIG. (141) “Vin rise?” After starting the engine, first, the main power supply voltage Vin is detected (capture of the detection output of the A / D converter 7a), and it is determined whether or not the power supply voltage Vin is rising. In the operation of this modified example, first, it is indispensable to detect the rise of the main power supply voltage Vin. Therefore, first,
It is detected whether or not the power supply voltage Vin is rising. When the determination result is No, the determination is repeated until the determination result of Yes is obtained.

(142) "Ti Timer Start" If the result of the determination in the above step (141) is Yes, that is, if the power supply voltage Vin rises, immediately after the start of the power supply voltage Vin, which is the elapsed time, the engine continues high. By starting the Ti timer that measures the time Ti, the high continuation Ti is started after the engine is started. (143) "Send Activation Signal to In-Vehicle Equipments 1, 2, 3" Next, the control circuit 18 transmits an activation signal to each in-vehicle Equipment 1, 2, 3. As a result, each in-vehicle device 31, 32, 3
3 starts.

(144) "Vin drop?" Next, it is determined whether the power supply voltage Vin has dropped. When the determination result is No, the determination is repeated until the determination result of Yes is obtained. (145) “Ti timer stop” When the determination result of the above step (144) is Yes, the high duration time Ti after engine start by the Ti timer is
Stop timing.

(146) "Ti <Timax?" The high continuation time Ti after starting the engine is compared with the high continuation maximum time Timax after starting the engine to determine whether or not the Ti is smaller than Timax. High continuation maximum time at startup Tima
x is the time Ti until the power supply voltage Vin after starting rises after the power supply voltage Vin after starting rises, which is a reference for determining that the engine has been started when the time is shorter than that in order to determine whether or not the engine has been started. That is as described above.

(147) "Tsmaxstart (1, 2, 3)
Setting ”When the determination result of the step (146) is Yes, that is, when Ti <Timax, the engine is being started, and after the engine is started, the power supply voltage Vin is reduced for a short time Ts. As a comparison reference Tsmax for determining whether to disconnect or stop the power supply, Tsmaxstart1 for the in-vehicle device 31 and Tsmax for the in-vehicle device 32 are used.
smaxstart2, Tsmaxstart for in-vehicle device 33
Set 3. (148) “Tsmax normal setting” If the determination result of the above step (146) is No, that is, if Ti> Timax, it is not when the engine is started, and in this case, the power supply voltage Vin decreases. As the comparison reference Tsmax in the comparison for determining whether there is a momentary interruption or a power stop for the time Ts, Tsmaxnormal1 is set for the vehicle-mounted device 31, Tsmaxnormal2 is set for the vehicle-mounted device 32, and Tsmaxnormal3 is set for the vehicle-mounted device 33.

(149) "Activation of Ts timer" Next, the lowering state duration time Ts of the main power supply voltage Vin
Start the Ts timer that keeps time. That is, the timing of Ts is started. (150) “Ts> Tsmax1?” Then, the lowered state duration time Ts is the step (147) for the vehicle-mounted device 31 [when the engine is started:
The value set as Tsmax1 (Tsmaxstart1) when the determination result of Yes is obtained in step (146)] or step (148) [In the normal case: When the determination result of No is obtained in step (146)] Or T
It is determined whether smaxnormal1) is exceeded.

(151) "Vin drop?" When the result of the determination in step (149) is No,
It is determined whether the main power supply voltage Vin has dropped. Then, when the determination result is Yes, step (15
Return to 0). (152) “Send Stop Signal to In-Vehicle Equipment 31” When the determination result in step (150) is Yes, the stop signal for supplying the power supply voltage is sent to the in-vehicle apparatus 31. When the vehicle-mounted device 31 receives the stop signal, the vehicle-mounted device 31 forms a state in which no problem occurs even if the supply of the power supply voltage is stopped. A shutdown waiting time Tw1 is required to form this state.

(153) "Stop the in-vehicle device 31 after Tw1" After the stop signal is transmitted in step (125), the shutdown waiting time Tw1 of the in-vehicle device 31 is measured, and after the time Tw1 has elapsed, the power supply controller 17 performs the in-vehicle operation. Equipment 3
The supply of the power supply voltage to 1 is stopped. (154) “Ts> Tsmax2?” Then, the reduced state duration time Ts is the step (147) [when the engine is started:
The value (Tsmaxstart2) set as Tsmax2 in the case where the determination result of Yes is obtained in step (146)] or in the step (148) [in the normal case: when the determination result of No is obtained in step (146)] Or T
It is determined whether smaxnormal2) is exceeded.

(155) "Vin drop?" If the determination result of the above step (154) is No,
It is determined whether the main power supply voltage Vin has dropped. Then, when the determination result is Yes, step (15
Return to 4). (156) "Send Stop Signal to In-Vehicle Equipment 31" If the determination result in step (154) is Yes, the stop signal for supplying the power supply voltage is sent to the in-vehicle apparatus 32. When the vehicle-mounted device 32 receives the stop signal, the vehicle-mounted device 32 forms a state in which no problem occurs even if the supply of the power supply voltage is stopped. A shutdown waiting time Tw2 is required to form this state.

(157) "Stop the in-vehicle device 32 after Tw2" After the stop signal is transmitted in step (125), the shutdown waiting time Tw2 of the in-vehicle device 32 is measured, and after the time Tw2 has elapsed, the power supply controller 17 performs the in-vehicle operation. Equipment 3
The supply of the power supply voltage to 2 is stopped. (158) “Ts> Tsmax3?” Then, the lowered state duration time Ts is the same as the step (147) for the in-vehicle device 33 [when the engine is started:
The value set as Tsmax3 (Tsmaxstart3) when the determination result of Yes is obtained in step (146)] or step (148) [In the normal case: When the determination result of No is obtained in step (146)] Or T
It is determined whether smaxnormal3) is exceeded.

(159) "Vin drop?" If the determination result of the above step (158) is No,
It is determined whether the main power supply voltage Vin has dropped. Then, when the determination result is Yes, step (15
Return to 8). (160) “Send Stop Signal to In-Vehicle Equipment 33” When the determination result in step (158) is Yes, the stop signal for supplying the power supply voltage is sent to the in-vehicle apparatus 33. When the vehicle-mounted device 33 receives the stop signal, it forms a state in which no problem occurs even if the supply of the power supply voltage is stopped. A shutdown waiting time Tw3 is required to form this state.

(161) "Stop the in-vehicle device 33 after Tw3" After transmitting the stop signal in step (125), the shutdown waiting time Tw3 of the in-vehicle device 33 is measured, and after the time Tw3 has elapsed, the power supply controller 17 performs the in-vehicle operation. Equipment 3
The supply of the power supply voltage to 3 is stopped. Then, this flow is ended, or the process returns to the step (141). (162) “Send start signal to in-vehicle devices 31 to 33” When the determination result in the above step (151), (155) or (159) is No, each in-vehicle device 31 to 33
3. Send start signal to 3. Then, each in-vehicle device 31 to 3
3 starts. Then, the step (12
Return to 1).

According to such a modification, the main power supply voltage Vin is measured, and when it rises, the timing of Ti is started from the start of the rise, and the Ti when the power supply voltage Vin is lowered. Is greater than a preset Timax, and when Yes is determined to be engine start, Tsmaxstart (Tsmaxstart1, 2, 3) corresponding to each in-vehicle device 3 as a reference for comparison with the decrease time Ts. On the contrary, when the determination is No, it is determined that it is not after the engine is started, and Tsmaxnormal corresponding to each in-vehicle device 3 is set.
(Tsmaxnormal1, 2, 3) is set. After that, the time counting of the time Ts after the power supply voltage Vin is lowered is started. Then, the time Ts is the above Tsmaxstart or T
It is determined whether it is larger than smaxnormal. When the determination result is No, the drop is merely a momentary interruption, and the normal state of supplying the power supply voltage to the vehicle-mounted devices 31 to 33 is restored.

Then, the determination result as to whether or not the time Ts is larger than Tsmaxstart or Tsmaxnormal is Yes.
When it occurs, it can be said that the deterioration of the in-vehicle device 3 related to the determination result is not a simple interruption, so the power supply to the in-vehicle device 3 is stopped. Such a flow is sequentially performed for the vehicle-mounted devices 31, 32, 33. Therefore,
The power supply to the vehicle-mounted device 3 in which the result recognized as an instantaneous interruption has occurred is stopped. That is, the transmission of the power supply voltage from the output that supplies the power supply voltage to the vehicle-mounted device 3 is stopped (the main power supply voltage Vin and the output voltage of the backup battery are not output).

When Ts <Tsmax and the power supply voltage Vin drops momentarily, the waveforms of the power supply voltage Vin and the power supply voltage output from the power supply switching section corresponding to the on-vehicle device 3 are shown in FIG. ), And if the result of the determination as to whether or not the time Ts is greater than Tsmaxstartn or Tsmaxnormaln is Yes, and it can be said that the time Ts is not a simple interruption, the power supply voltage Vin and the power supply output from one output The waveform of the voltage is as shown in FIG. 18 (B), and Ti> Timax, that is, not after the engine is started, and even if the power supply voltage Vin decreases, the time Ts is smaller than Tsmax, and there is a momentary interruption. When the determination is made and the supply of the power supply voltage is not stopped but continued, the waveform is as shown in FIG.

[0143]

According to the on-vehicle power supply control device of the first aspect,
When the power supply voltage from the vehicle battery drops, the power supply voltage from the backup battery is supplied to the vehicle equipment,
Whether or not there is a momentary interruption is determined by comparing the time duration Ts of the reduced state of the power supply voltage from the vehicle battery with the maximum momentary interruption time Tsmax set as the maximum time of the range expected to be an instantaneous interruption, and the state of decrease is determined. The duration Ts is the maximum instantaneous time Tsma
If it is x or less, it is considered as a momentary interruption, and when the power supply voltage rises, the backup is stopped and the power supply voltage from the vehicle battery is supplied to the vehicle equipment in the normal state. Conversely, if the reduced state duration Ts is the instantaneous maximum time Tsmax or more As the power supply voltage from the vehicle-mounted battery is stopped, the supply of the power supply voltage to the vehicle-mounted device is stopped (backup is stopped), and it is possible to prevent the remaining charge of the backup battery from being unnecessarily reduced.

According to the on-vehicle power source control device of the second aspect, when the power source of a plurality of on-vehicle devices is controlled, the power source voltage can be separately supplied to each of the plurality of on-vehicle devices.
As the maximum instantaneous interruption time Tsmax, different times Tsmaxn (n: 1, 2, ...
・) Is set, it is possible to set different criteria depending on the degree of caution required, without uniformly setting the criteria for instantaneous interruption for each in-vehicle device.

According to the on-vehicle power supply control device of the third aspect, when the power supply voltage from the on-vehicle battery rises, the time Ti is measured until the power supply voltage decreases and then the time T.
Whether or not the engine is started is determined depending on whether i is shorter or longer than the maximum continuous high time Timax after starting, and whether or not the subsequent lowering state duration Ts is exceeded is detected according to the determination result. Time Tsmax is Tsm in the former case
axstart or Tsmaxstart n (n:
1, 2, ...) In the latter case, for example, a shorter Tsmaxnormal or a different Tsmaxnormal for each in-vehicle device.
Since it is set to n (n: 1, 2, ...),
It is possible to prevent the interruption of the power supply voltage from the vehicle-mounted battery from being determined as the interruption of the power-supply voltage from the vehicle-mounted battery due to the instantaneous interruption that occurs after the engine is started.

According to the on-vehicle power supply control device of the fourth aspect, the lowered state duration time Ts is the preset maximum instantaneous interruption time Ts.
When the result of detecting that the lowered state continues even after max or Tsmaxn elapses and the output of the power supply voltage to the vehicle-mounted device is stopped, the stop is performed after the shutdown waiting time Tw has elapsed from the detection time. Therefore, even if it is confirmed that the supply of the power supply voltage from the vehicle-mounted battery is stopped, the backup battery continues to be backed up until the shutdown standby time Tw elapses. Can be prevented.

According to the on-vehicle power source control device of the fifth aspect, when the power source of a plurality of vehicle-mounted devices is controlled, the power source voltage can be separately supplied to each of the plurality of vehicle-mounted devices, and the shutdown standby time Tw is set as the above. Different times Tsmaxn (n: 1, 2, ...)
・ ・) Is set, so that it is possible to cope with the difference in characteristics and specifications of each in-vehicle device, especially when the supply of the power supply voltage is stopped.

According to the on-vehicle power supply control device of the sixth aspect, when the power supply voltage from the on-vehicle battery drops, the power supply voltage from the backup battery is supplied to the on-vehicle equipment, and whether or not there is a momentary interruption is checked by the power supply voltage from the on-vehicle battery. The decrease state duration Ts is compared with the maximum interruption time Tsmax set as the maximum time in the range expected to be an instantaneous interruption, and the decrease state duration Ts is determined to be the maximum instantaneous time Tsmax.
If it is less than the following, it is regarded as a momentary interruption, and when the power supply voltage rises, the backup is stopped and the power supply voltage from the on-vehicle battery is supplied to the in-vehicle device in the normal state. Conversely, if the lowered state duration time Ts is the instantaneous maximum time Tsmax or more As the power supply voltage from the battery is stopped, the supply of the power supply voltage to the vehicle-mounted device is stopped (backup is stopped) to prevent the remaining charge of the backup battery from being unnecessarily reduced.

According to the on-vehicle power source control device of the seventh aspect, in the on-vehicle power source control device of the sixth aspect, when the power source of a plurality of on-vehicle devices is controlled, the power source voltage is separately supplied to each of the plurality of on-vehicle devices. The maximum interruption time T
Since a different time Tsmaxn (n: 1, 2, ...) Is set as smax corresponding to each of the plurality of in-vehicle devices, the criterion of instantaneous interruption is not uniformly determined for each in-vehicle device. It can vary depending on the degree of prudence required.

According to the on-vehicle power supply control device of the eighth aspect, in the on-vehicle power supply control device of the sixth or seventh aspect, when the power supply voltage from the on-vehicle battery rises, the time Ti is measured until it decreases. If the time Ti is shorter or longer than the maximum high continuous time Timax after starting,
It is determined whether or not the engine is started, and according to the determination result, the maximum instantaneous interruption time Tsmax for detecting whether or not the subsequent lowering state duration time Ts has been exceeded. In the former case, Tsmax or Tsmaxn (n: 1 In the latter case, Tsmax0, which is shorter than that in the latter case, is set to a different value. Therefore, it is determined that the instantaneous interruption that occurs after the engine is started is the stop of the supply of the power supply voltage from the on-vehicle battery to the on-vehicle equipment. It is possible to prevent the supply of the power supply voltage from being stopped.

According to the on-vehicle power supply control device of the ninth aspect, since there is an OR circuit that receives the power supply voltage from the on-vehicle battery and the power supply voltage from the backup battery, the on-vehicle battery can be operated only by turning on the switch means at the subsequent stage. It is possible to form a state in which a backup battery backs up a drop in the power supply voltage, and to determine whether or not there is a momentary interruption, the duration time Ts in which the power supply voltage is reduced from the vehicle battery is the maximum time in the range expected to be a momentary interruption. Judgment is made by comparing with the set maximum interruption time Tsmax. If the lowered state duration time Ts is less than the maximum moment Tsmax, it is judged as an interruption, and the backup is stopped with the rise of the power supply voltage, and the power supply voltage from the on-board battery is stopped. To the normal state to supply to the in-vehicle equipment,
On the contrary, if the duration Ts of the lowered state is equal to or longer than the maximum instantaneous time Tsmax, the supply voltage of the on-vehicle battery is stopped and the supply of the power voltage to the on-vehicle device is stopped (stop of backup), and the remaining charge of the backup battery is wasted. Can be prevented.

According to the on-vehicle power source control device of claim 10,
The in-vehicle power supply control device according to claim 9, wherein when controlling the power supply of a plurality of in-vehicle devices, it is possible to separately supply a power supply voltage to each of the plurality of in-vehicle devices, and the plurality of in-vehicle devices are set as the instantaneous interruption maximum time Tsmax. Since a different time Tsmaxn (n: 1, 2, ...) Is set corresponding to each device, the criterion of instantaneous interruption is not uniformly set for each in-vehicle device, and the necessary caution is taken. It can be different depending on.

According to the vehicle-mounted power source control device of claim 11,
The on-vehicle power supply control device according to claim 9 or 10, wherein when a power supply voltage from the on-vehicle battery rises, a time Ti is measured until the power supply voltage decreases, and the time T is counted.
Whether or not the engine is started is determined depending on whether i is shorter or longer than the maximum continuous high time Timax after starting, and whether or not the subsequent lowering state duration Ts is exceeded is detected according to the determination result. Time Tsmax is Tsm in the former case
axstart or Tsmaxstart n (n:
1, 2, ...) In the latter case, for example, a shorter Tsmaxnormal or a different Tsmaxnormal for each in-vehicle device.
Since it is set to n (n: 1, 2, ...),
It is possible to prevent the interruption of the power supply voltage from the vehicle-mounted battery from being determined as the interruption of the power-supply voltage from the vehicle-mounted battery due to the instantaneous interruption that occurs after the engine is started.

According to the on-vehicle power supply controller of claim 12,
Whether or not there is a momentary interruption is determined by comparing the time duration Ts of the reduced state of the power supply voltage from the vehicle battery with the maximum momentary interruption time Tsmax set as the maximum time of the range expected to be an instantaneous interruption, and the state of decrease is determined. The duration Ts is the maximum instantaneous time Tsma
If it is x or less, it is considered as a momentary interruption, and when the power supply voltage rises, the backup is stopped and the power supply voltage from the vehicle battery is supplied to the vehicle equipment in the normal state. Conversely, if the reduced state duration Ts is the instantaneous maximum time Tsmax or more To stop the power supply voltage from the vehicle-mounted battery, the control circuit sends a control signal to the vehicle-mounted device to turn off the power supply, and also stops the supply of the power supply voltage from the switching means (stops the backup) to waste the remaining charge of the backup battery. Can be prevented.

According to the vehicle-mounted power source control device of claim 13,
13. The on-vehicle power supply control device according to claim 12, wherein when power control of a plurality of on-vehicle devices is performed, a power supply voltage can be separately supplied to each of the plurality of on-vehicle devices, and the plurality of on-vehicle devices are set as the instantaneous interruption time Tsmax. Since a different time Tsmaxn (n: 1, 2, ...) Is set corresponding to each device, the criterion of instantaneous interruption is not uniformly set for each in-vehicle device, and the necessary caution is taken. It can be different depending on.

According to the on-vehicle power supply control device of claim 14,
The vehicle-mounted power supply control device according to claim 12,
When the power supply voltage from the on-vehicle battery rises, the time Ti is measured until it decreases, and it is determined whether the engine is started or not depending on whether the time Ti is shorter or longer than the high continuous maximum time Timax after starting. , The maximum instantaneous interruption time Tsmax for detecting whether or not the subsequent lowering state duration time Ts is exceeded according to the determination result, and in the case of the former, Tsm
axstart or Tsmaxstart n (n:
1, 2, ...) In the latter case, for example, a shorter Tsmaxnormal or a different Tsmaxnormal for each in-vehicle device.
Since it is set to n (n: 1, 2, ...),
It is possible to prevent the interruption of the power supply voltage from the vehicle-mounted battery from being determined as the interruption of the power-supply voltage from the vehicle-mounted battery due to the instantaneous interruption that occurs after the engine is started.

According to the on-vehicle power source control device of claim 15,
Claims 6, 7, 8, 9, 10, 11, 12, 13 or 1
In the vehicle-mounted power supply control device according to 4, the lowering state duration time Ts has a preset instantaneous interruption maximum time Tsmax or Tsmax.
When the output of the power supply voltage to the in-vehicle device is stopped due to the detection result that the lowered state continues even after n has elapsed, the stop is performed after the shutdown standby time Tw has elapsed from the detection time. Therefore, even if it is confirmed that the supply of the power supply voltage from the vehicle-mounted battery is stopped, the backup battery continues to be backed up until the shutdown standby time Tw elapses, so that the vehicle-mounted device is prevented from malfunctioning due to the supply of the power supply voltage being stopped. be able to.

According to the on-vehicle power supply control device of claim 16,
Claims 6, 7, 8, 9, 10, 11, 12, 13, 14
Alternatively, in the in-vehicle power supply control device according to 15, when power control of a plurality of in-vehicle devices is performed, a power supply voltage can be separately supplied to each of the plurality of in-vehicle devices, and a shutdown standby time Tw is set for each of the plurality of in-vehicle devices. Since a different time Tsmaxn (n: 1, 2, ...) Is set in correspondence with that, it is possible to cope with the difference in characteristics and specifications of each in-vehicle device, especially when the supply of the power supply voltage is stopped. .

[Brief description of drawings]

1A and 1B show a first embodiment of an in-vehicle power supply control device of the present invention, FIG. 1A is a schematic system diagram of an electric system in a vehicle, and FIG. 1B is in-vehicle power supply control. It is a schematic block diagram of an apparatus.

FIG. 2 is a flowchart showing the operation of the first embodiment.

3A and 3B are waveform charts showing a main power supply voltage Vin and an output voltage of a vehicle-mounted power supply control device in each operation example of the first embodiment.

FIG. 4 is a flowchart showing an operation of a modified example of the first embodiment.

5A to 5C are waveform diagrams showing a main power supply voltage Vin and an output voltage of the vehicle-mounted power supply control device in each of the different operation examples in the modification example of FIG. 4.

6 (A) to 6 (C) show a second embodiment of the in-vehicle power supply control device of the present invention, (A) is a schematic system diagram of an electric system in a vehicle, and (B) is in-vehicle power supply control. FIG. 2 is a configuration diagram of a power supply distribution unit that constitutes the device, and FIG. 3C is a schematic configuration diagram of each power supply switching unit that constitutes the vehicle-mounted power supply control device.

FIG. 7 is a flowchart showing the operation of the second embodiment.

8A and 8B are waveform charts showing a main power supply voltage Vin and an output voltage of an in-vehicle power supply control device in each operation example of the second embodiment.

FIG. 9 is a flowchart showing an operation of a modified example of the second embodiment.

10A to 10C are waveform diagrams showing the main power supply voltage Vin and the output voltage of the vehicle-mounted power supply control device in each operation example of the modification shown in FIG. 9.

11A and 11B show a third embodiment of the on-vehicle power supply control device of the present invention, FIG. 11A is a schematic system diagram of an electric system in a vehicle, and FIG. 11B is on-board power supply control. It is a schematic block diagram of an apparatus.

FIG. 12 is a flowchart showing an operation of the third embodiment of the vehicle-mounted power supply control device of the present invention.

FIG. 13 is a flowchart showing an operation of a modified example of the third embodiment.

FIGS. 14A and 14B show the fourth embodiment, and FIG. 14A is a schematic system diagram of an electric system in an automobile.
(B) is a schematic block diagram of a vehicle-mounted power supply control device.

FIG. 15 is a flowchart showing the operation of the fourth embodiment.

16 (A) and 16 (B) are waveform charts showing a main power supply voltage Vin, an output voltage of a vehicle-mounted power supply control device, and a control signal in another operation example of the fourth embodiment.

FIG. 17 is a flowchart showing an operation of a modified example of the fourth embodiment.

18A to 18C are waveform charts showing a main power supply voltage Vin, an output voltage of a vehicle-mounted power supply control device, and a control signal in another operation example of the modification of the fourth embodiment.

[Explanation of symbols]

1a, 1b ... In-vehicle power supply control device, 2 ... In-vehicle battery, 31-33 ... In-vehicle device, 31 ... Car audio device, 32 ... Car navigation device, 33
... Security system, 4, 14 ... Voltage drop determination means, power supply voltage high determination means (CPU), 7 ...
Power supply voltage detection means (A / D converter), 8 ... Backup battery, SW ... Switching means, 17 ... Power supply switching means (power supply controller), 18 ... Control circuit.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H02J 9/06 503 H02J 9/06 503B 503E

Claims (16)

[Claims] 1. An on-vehicle power supply control device for controlling the supply of a power supply voltage to at least a part of an on-vehicle device that receives a power supply voltage from an on-vehicle battery, the power supply voltage from the on-vehicle battery having at least a backup battery. When the power supply voltage drops from the backup battery to the vehicle-mounted device when the power supply voltage drops, the lowering state duration time Ts is detected and the lowering state duration time Ts is set to a preset instantaneous interruption maximum. It is detected whether the power supply voltage from the vehicle-mounted battery rises within a time shorter than the time Tsmax or whether the lowering state continues even after the maximum instantaneous interruption time Tsmax has passed. If the result of the detection is the former, The power supply voltage from the on-vehicle battery is output to the on-vehicle equipment, and the backup state is canceled. Expediently, vehicle power supply control apparatus characterized by comprising so as to stop the output of the power supply voltage to the in-vehicle equipment. 2. A power supply voltage can be separately supplied to each of a plurality of on-vehicle devices, and a different time Tsmaxn (n: 1, 2) corresponding to each of the plurality of on-vehicle devices is set as the instantaneous interruption maximum time Tsmax. , ...
・) Is set, and the maximum instantaneous interruption time Tsmax set for each in-vehicle device
The time Ts exceeding n is set such that each time the power supply voltage continues to decrease, the output of the voltage to the in-vehicle device corresponding to the instantaneous interruption maximum time Tsmaxn is stopped. In-vehicle power supply control device described. 3. When the power supply voltage from the vehicle-mounted battery rises, the time Ti is measured until it decreases, and the backup state is formed after the time Ti falls, and whether the reduced state duration time Ts is exceeded later. If the time count Ti is shorter than the high continuous maximum time Timax after starting as the instantaneous interruption maximum time Tsmax for detecting whether or not it is Tsmax.
start or Tsmaxstartn (n:
1, 2, ...) is smaxnormal in the case of a long time or Tsmaxnormaln (n: 1, 2, ...
3.) The vehicle-mounted power supply control device according to claim 1 or 2, wherein the value of () can be set to a different value depending on the above case. 4. When the output of the power supply voltage to the in-vehicle device is stopped, the stop is performed after a shutdown waiting time Tw has elapsed from the time of detection thereof. Alternatively, the vehicle-mounted power supply control device according to the above item 3. 5. A power supply voltage can be separately supplied to a plurality of vehicle-mounted devices, and the shutdown standby time Tw is different for each of the plurality of vehicle-mounted devices and corresponds to a different time Tsmaxn (n:
1, 2, ...) is set, The vehicle-mounted power supply control device according to claim 4, wherein 6. An in-vehicle power supply control device for controlling the supply of a power supply voltage to at least a part of an in-vehicle device that receives a power supply voltage from an in-vehicle battery, the power supply voltage detecting means detecting a power supply voltage of an in-vehicle battery, When the backup battery and the power supply voltage output from the power supply voltage detecting means are decreased, the measurement of the lowered state duration time Ts is started, and the power supply voltage of the above-mentioned power supply voltage is maintained even after the preset maximum interruption time Tsmax has elapsed. Power supply voltage drop determining means for determining whether or not the voltage continues to drop, a switching state for outputting the power supply voltage from the vehicle-mounted battery, a switching state for outputting the output voltage from the backup battery, and no voltage output And a switching means for controlling the state switching between the switching state and the switching state. When the power supply voltage from the vehicle-mounted battery drops, the switching means is switched to a state in which the output voltage from the backup battery is output, and the maximum power interruption time Tsma is output from the power supply voltage drop determining means.
The vehicle-mounted power source characterized in that when a result of the determination that the power supply voltage continues to decrease even after a time exceeding x has occurred, the switching means is set to a switching state in which no voltage is output. Control device. 7. The power supply voltage can be separately supplied from the switching means to a plurality of vehicle-mounted devices, and a different time Tsmaxn (n: 1, n: 2, ...
.) Is set, and each time the judgment result that the time Ts exceeding the maximum interruption time Tsmaxn set for each in-vehicle device is set by the determination means and the power supply voltage continues to decrease, the maximum interruption 7. The in-vehicle power supply control device according to claim 6, wherein the switching means is controlled so as to stop the output of the power supply voltage to the in-vehicle device corresponding to the time Tsmaxn. 8. A high continuation time T after engine start when the power supply voltage output from the power supply voltage detecting means rises.
a power supply voltage high determination means for determining whether or not the power supply voltage continues to be in a high state even after a preset time for starting the high continuation time Timax has elapsed after the start of time measurement of i, When the power supply voltage from the vehicle battery rises, the high continuation time Ti is measured after the engine is started, and
When the backup time is formed after the power supply voltage drops, and the above-mentioned clock time Ti is shorter than the maximum continuous time Timax after starting as the instantaneous interruption maximum time Tsmax for detecting whether or not the decreased state duration time Ts is exceeded later. Has Tsmax
start or Tsmaxstartn (n:
1, 2, ...) is smaxnormal in the case of a long time or Tsmaxnormaln (n: 1, 2, ...
8.) The vehicle-mounted power supply control device according to claim 6 or 7, wherein the value can be set to a different value depending on the above case. 9. An on-vehicle power supply control device for controlling supply of a power supply voltage to at least a part of an on-vehicle device that receives a power supply voltage from the on-vehicle battery, wherein the on-vehicle battery supplies a power supply voltage to each of the on-vehicle devices and a backup battery. A power supply distribution unit that distributes both the power supply voltage from the power supply unit and a power supply switching unit that is provided corresponding to each of the in-vehicle devices. Each power supply switching unit is a power supply that detects the power supply voltage of the in-vehicle battery. At least a voltage detection means, an OR circuit that receives the power supply voltage from the vehicle-mounted battery and the power supply voltage from the backup battery and outputs the higher one, and a switch means provided on the output side of the OR circuit. The switch means is the power supply voltage detection means that is built in an in-vehicle device corresponding to the power supply switching unit to which the switch means belongs. And starts counting the degraded state duration Ts when the output power supply voltage is lowered, interruption maximum time T set in advance
Controlled by a power supply voltage drop determining means for determining whether or not the power supply voltage continues to drop even after a time period exceeding smax has passed. Normally, the switch means outputs the output power supply voltage from the OR circuit. The switch means is turned off when the result of the determination that the power supply voltage continues to decrease even after the lapse of the maximum instantaneous interruption time has passed from the power supply voltage decrease determining means. An in-vehicle power supply control device characterized by the above. 10. The OR circuit and the switch means are provided corresponding to a plurality of vehicle-mounted devices, and different times Tsmaxn (n: 1, 2) corresponding to each of the plurality of vehicle-mounted devices are set as instantaneous interruption maximum time Tsmax. , ...
.) Is set, and each time the judgment result that the time Ts exceeding the maximum interruption time Tsmaxn set for each in-vehicle device is set by the determination means and the power supply voltage continues to decrease, the maximum interruption 10. The in-vehicle power supply control device according to claim 9, wherein the switch means is controlled so as to stop the output of the voltage to the in-vehicle device corresponding to the time Tsmaxn. 11. When the power supply voltage output from the power supply voltage detecting means rises, the timing of the high continuation time Ti after engine start is started, and a time exceeding a preset maximum high continuation time Timax after start elapses. Even if the power supply voltage high determination means for determining whether or not the power supply voltage is still high is provided, and when the power supply voltage from the vehicle-mounted battery rises, the high continuation time Ti after engine start is clocked. If the measured time Ti is shorter than the high continuous maximum time Timax after starting as the maximum instantaneous disconnection time Tsmax for detecting whether or not the lowering state continuous time Ts has exceeded afterwards, Tsmax
start or Tsmaxstartn (n:
1, 2, ...) is smaxnormal in the case of a long time or Tsmaxnormaln (n: 1, 2, ...
The vehicle-mounted power supply control device according to claim 9 or 10, wherein the value of () can be set to a different value depending on the above case. 12. An in-vehicle power supply control device for controlling the supply of a power supply voltage to at least a part of an in-vehicle device that receives a power supply voltage from an in-vehicle battery, the power supply voltage detecting means detecting a power supply voltage of an in-vehicle battery, A backup battery, a switching means for receiving the power supply voltage from the on-vehicle battery and the power supply voltage from the backup battery, and outputting the power supply voltage corresponding to the received control signal to the on-vehicle equipment, and the power supply voltage from the switching means. A control circuit that sends a control signal for controlling on / off of power to the on-vehicle device that receives the power supply, and when the power supply voltage output from the power supply voltage detection means decreases, starts measuring the reduced state duration Ts. , Whether the power supply voltage continues to drop even after the preset maximum instantaneous interruption time Tsmax has elapsed Power source voltage drop determining means for determining is provided, and normally, the switching means is set to a state in which the power source voltage from the on-vehicle battery is output, and when the power source voltage from the on-vehicle battery decreases, the switching means is changed from the backup battery. The output voltage is switched to the output state, and the maximum power interruption time Tsma
If a result of the determination that the power supply voltage continues to decrease even after the time exceeding x has passed, the switching means is switched to a state in which no voltage is output, and the power is supplied from the control circuit to the in-vehicle device. An in-vehicle power supply control device characterized in that a stop signal for turning it off is transmitted. 13. A power source voltage can be separately supplied from the switching means to a plurality of vehicle-mounted devices, and a different time Tsmaxn (n: 1, n: 2, ...
.) Is set, and each time the judgment result that the time Ts exceeding the maximum interruption time Tsmaxn set for each in-vehicle device is set by the determination means and the power supply voltage continues to decrease, the maximum interruption 13. The in-vehicle power supply control device according to claim 12, wherein the switching means is controlled so as to stop the output of the power supply voltage to the in-vehicle device corresponding to the time Tsmaxn. 14. When the power source voltage output from the power source voltage detecting means rises, the timing of the high duration time Ti after engine start is started, and a time exceeding a preset high duration maximum time Timax after start has elapsed. Even if the power supply voltage high determination means for determining whether or not the power supply voltage continues to be high is provided, when the power supply voltage from the vehicle-mounted battery rises, the time Ti is measured until it decreases. With
When the above-mentioned backup state is formed after the decrease and the measured time Ti is shorter than the high continuous maximum time Timax after starting as the maximum instantaneous interruption time Tsmax for later detecting whether or not the decreased state duration Ts is exceeded, Tsmax
start or Tsmaxstartn (n:
1, 2, ...) is smaxnormal in the case of a long time or Tsmaxnormaln (n: 1, 2, ...
14. The vehicle-mounted power supply control device according to claim 12 or 13, wherein the value of () can be set to a different value depending on the above case. 15. The method according to claim 6, wherein when the output of the power supply voltage to the in-vehicle device is stopped, the stop is performed after the shutdown standby time Tw has elapsed from the detection time. , 8, 9, 10, 11, 1
The in-vehicle power supply control device according to 2, 13, or 14. 16. A power supply voltage can be separately supplied to each of a plurality of vehicle-mounted devices, and the shutdown standby time Tw is different for each of the plurality of vehicle-mounted devices and corresponds to a different time Tsmaxn (n:
1, 2, ...) are set. 6. The method according to claim 6, 7, 8, 9, 10, 11, 12, 13, 14 or 1.
5. The in-vehicle power supply control device described in 5.