JP2005289204A - Power supply control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply control device capable of reducing the dark current when an electrical unit is in a non-service condition. <P>SOLUTION: A power supply battery 110 is connected to an electrical unit from a power supply path including a relay circuit 120, and is also connected to an ignition switch 130. The other terminal of the ignition switch 130 is connected to a momentary switch 140. A starting power supply capacitor C2 is connected to the other terminal, and connected via a diode D2 toward a power supply terminal of a T flip-flop circuit 150. The power supply path is connected to the power supply terminal via a diode D3. In addition, the command signal is input in an input terminal of the T flip-flop circuit 150 via a resistor element R3 and a diode D1, and a Q output terminal controls the conduction of a MOS transistor 160. The relay circuit 120 is opened/closed to form the power supply path. If the momentary switch 140 is non-conductive, the power supply voltage is not applied to the power supply control device 1, and no dark current runs therein. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a power supply control device that performs power supply control to an electrical device in accordance with a usage state of the electrical device, and particularly relates to a power supply control device that performs power supply control to an in-vehicle electrical device.

  A power supply control device 100 shown in FIG. 7 is a power supply control device that has been conventionally used for power supply control to in-vehicle electrical equipment. In the on-vehicle power supply control device, since it is necessary to suppress the dark current from the power supply battery 110, a configuration is adopted in which the power supply path to the electrical equipment is cut off when the electrical equipment (not shown) is not used.

  This is the relay circuit 120 of FIG. When the ignition switch 130 is turned on, the power supply preparation state is entered, and the input of the momentary switch 140, which is a start switch of the electrical equipment, is awaited. In this configuration, power supply to the electrical equipment is controlled according to the conduction of the momentary switch 140.

  The power battery 110 is divided into two paths, one connected to the relay circuit 120 and the other connected to the power terminal of the toggle flip-flop circuit 150 via the ignition switch 130. When the ignition switch 130 is turned on, power is supplied to the flip-flop circuit 150. When the momentary switch 140 is turned on in this state, the power battery 110 is connected to the input terminal of the flip-flop circuit 150. A high level signal is input to the flip-flop circuit 150 and the output voltage is inverted to a high level. As a result, the MOS transistor 160 becomes conductive and the relay circuit 120 operates to supply power to the electrical equipment.

  At the end of use of the device, the momentary switch 140 is input again. Since the voltage from the battery 110 is supplied again to the input terminal of the flip-flop circuit 150, the output voltage is inverted and the MOS transistor 160 becomes non-conductive. The relay circuit 120 becomes non-conductive and power supply to the electrical equipment is interrupted.

  In addition, in the recording apparatus disclosed in Patent Document 1 as another related technique, the amount of power used when the recording apparatus is in a standby or power-off state is reduced.

JP 2003-94770 A

  In the background art described above, the dark current from the power supply battery 110 is suppressed by interrupting the power supply path to the electrical equipment when the electrical equipment is not used. However, the power supply control device needs to be supplied with power from the power supply battery 110 in order to control the interruption of the power supply path to the electrical equipment. For example, the flip-flop circuit 150 is maintained in a power supply state via the ignition switch 130. Is done. Dark current flows through the flip-flop circuit 150 and other circuits that are powered by the power supply battery 110. It is a problem that current consumption cannot be reduced when the electrical equipment is not used.

  The present invention has been made to solve the above-described problems of the prior art, and an object thereof is to provide a power supply control device capable of reducing dark current in an unused state of electrical equipment.

  In order to achieve the above object, a power supply control device according to claim 1 is connected to a power supply unit, and conducts in response to a power supply and non-power supply command to the electrical equipment, and commands a voltage signal from the power supply unit. A power supply control device including a command switch unit that inputs a signal includes a start power supply capacitor that charges a voltage signal from the power supply unit via the command switch unit, and the charge voltage charged in the start power supply capacitor serves as a power source in power supply initial control. It is used.

  In the power supply control device according to the first aspect, the voltage signal input from the power supply unit via the command switch unit is used as the power supply of the power supply control device in the initial stage of power supply. A charging voltage obtained by charging a voltage signal from the power supply unit to the starting power supply capacitor is used as a power supply to the power supply control device.

  As a result, power supply is supplied to the power supply control device by inputting power supply and non-power supply commands to the electrical equipment, and it is not necessary to supply power before the command. Dark current that flows through the power supply control device when the electrical equipment is not used can be eliminated, and current consumption can be reduced.

  According to a second aspect of the present invention, there is provided a power supply control device according to the first aspect, in which the first storage unit that stores the command signal and outputs the command signal as the power supply control signal, the starting power supply capacitor, and the first storage unit A second rectifier connected between the power supply terminal and supplying power to the power supply terminal; and a second rectifier connected between the power supply path to the electrical equipment and the power supply terminal of the first storage unit and supplying power to the power supply terminal. And a rectifying unit.

  In the power supply control device according to the second aspect, the command signal is stored in the first storage unit and is output as the power supply control signal. The power supply of the first storage unit is supplied from the starting power supply capacitor via the first rectification unit in the initial stage of power supply control, and then supplied from the power supply path to the electrical equipment via the second rectification unit. Here, due to the rectifying action of the second rectifying unit, the power supplied from the starting power supply capacitor does not flow into the power supply path of the electrical equipment, and the charging voltage of the starting power supply capacitor is efficiently supplied to the first storage unit. The In addition, the power supplied from the power supply path does not charge the startup power supply capacitor by the rectifying action of the first rectification unit, and the command signal is not erroneously output by charging the startup power supply capacitor.

  As a result, at the initial stage of power supply accompanying the power supply and non-power supply commands, power is supplied from the starting power supply capacitor, and after the power supply state is established, power is supplied from the power supply path and the power supply state is maintained.

  According to a third aspect of the present invention, there is provided a power supply control device according to the first aspect, wherein the initial power supply control unit outputs a power supply initial control signal at the initial stage of power supply from the input of the command signal using the charging voltage as a power source. And a second storage unit that is supplied with power based on the power supplied to the electrical equipment, stores a command signal, and outputs the command signal as a power supply maintenance control signal.

  In the power supply control device according to the third aspect, the initial power supply control unit outputs a power supply initial control signal in the initial power supply from the input of the command signal. The power at this time is supplied from the starting power supply capacitor. After power supply to the electrical equipment is started, the second storage unit is supplied with power based on the supplied power and outputs the stored command signal as a power supply maintenance control signal.

  As a result, in the initial stage of power supply accompanying power supply and non-power supply commands, power is supplied from the start power supply capacitor and a power supply initial control signal is output.After the power supply state is established, power is supplied from the power supply path. A power supply maintenance control signal is output.

  The power supply control device according to claim 4 is the power supply control device according to claim 3, wherein the initial power supply control unit controls the initial power supply in accordance with the power supply voltage value supplied based on the power supplied to the electrical equipment. An inactive portion that inactivates the signal is provided.

  As a result, the inactive part detects that the power supply to the electrical equipment has been started according to the power supply voltage value supplied based on the supplied power, and controls the initial power supply control part to Active. The operation period of the initial power supply control unit can be the initial stage of power supply from the input of the command signal to the detection of power supply to the electrical equipment.

  The power supply control device according to claim 5 is the power supply control device according to claim 3 or 4, wherein the second storage unit is configured to issue a command according to the power supply voltage value supplied based on the power supplied to the electrical equipment. A trigger unit for starting a signal storing operation is provided.

  As a result, the timing for fetching the command signal to the second storage unit can be set after the power supply to the second storage unit is reliably performed, and the command signal is reliably stored in the second storage unit. Can be done.

  The power supply control device according to claim 6 is the power supply control device according to claim 2 or 3, wherein the power supply control device is connected to the starting power supply capacitor in the input path of the command signal, and the voltage is compared with the voltage transition of the charging voltage. A signal transition delay unit that outputs a signal with delayed transition as a command signal is provided.

  As a result, the signal transition delay unit outputs a signal that transitions with a delay after the voltage transition of the charging voltage to the starting power supply capacitor as a command signal. A signal is input, and reliable control can be performed on the command signal.

  According to a seventh aspect of the present invention, in the power supply control device according to the first aspect, the power supply control device includes a discharge unit that discharges the charging voltage charged in the starting power supply capacitor after a predetermined time. As a result, the starting power supply capacitor can be initialized by discharging the charging voltage charged in the starting power supply capacitor from the power supply unit via the command switch unit.

  The power supply control device according to claim 8 is the power supply control device according to at least one of claims 1 to 7, wherein the power supply unit is a vehicle battery, and the electrical equipment is an in-vehicle electrical equipment. Is preferred. Thereby, when the electrical equipment is not used, the power consumption from the vehicle battery can be reduced, which can contribute to the extension of the battery life.

  According to the present invention, the power supply voltage is supplied together with the command signal to the control circuit in accordance with the power supply and non-power supply commands of the electrical equipment, and the power supply to the control circuit is stopped when the command is not input. It is possible to provide a power supply control device that can eliminate the dark current flowing through the control circuit when the device is not used and can reduce current consumption.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the power supply control device of the present invention will be described below in detail with reference to the drawings based on FIGS. In the following embodiments, a case where the power supply control device of the present invention is applied to power supply control to an in-vehicle electrical equipment will be described as an example.

  In the power supply control device 1 of the first embodiment shown in FIG. 1, a power supply battery 110 that is an example of a power supply unit or a vehicle battery is connected to a switch terminal of the relay circuit 120 via a fuse element 170. The other end is connected to an electric equipment (not shown) as a power supply path. When the switch of relay circuit 120 is relay-connected, power is supplied from power supply battery 110 to the electrical equipment.

  The power battery 110 is further connected to one terminal of the ignition switch 130 via the fuse element 180. The other terminal of the ignition switch 130 is connected to one control terminal of the relay circuit 120 and to one terminal of a momentary switch 140 that is an example of a command switch unit. Here, the control terminal of the relay circuit 120 is a terminal that controls relay connection. The ignition switch 130 is turned on by a key operation on the vehicle. By pressing the momentary switch 140 in this state, the start and stop of power supply to the electrical equipment are controlled.

  The starting power supply capacitor C2 is connected between the other terminal of the momentary switch 140 and the ground potential, and a toggle flip-flop circuit (hereinafter referred to as a T flip-flop circuit) 150 that is an example of the first storage unit. A diode D2, which is an example of a first rectification unit, is connected in the forward direction toward the power supply terminal. That is, the starting power supply capacitor C2 and the anode terminal of the diode D2 are connected, and the cathode terminal of the diode D2 and the power supply terminal of the T flip-flop circuit 150 are connected. Similarly, the power supply path from the relay circuit 120 to the electrical equipment is connected to the anode terminal of the diode D3 which is an example of the second rectification unit, and the cathode terminal of the diode D3 and the power supply terminal of the T flip-flop circuit 150 are connected. The diode D3 is forward-connected from the power supply path toward the power supply terminal.

  Further, the other terminal of the momentary switch 140 is connected to the toggle input terminal of the T flip-flop circuit 150 via the resistance element R3 and the diode D1. A capacitor C1 and a resistance element R1 are connected to the toggle input terminal between the ground potential. The starting power supply capacitor C2 is discharged along a path from the resistance element R3 to the ground potential via the diode D1 and the resistance element R1. The resistor element R3, the diode D1, and the resistor element R1 constitute an example of a discharge unit.

  The Q output terminal of the T flip-flop circuit 150 is connected to the gate terminal of the MOS transistor 160. The MOS transistor 160 is connected to the other control terminal of the relay circuit 120. Due to the conduction of the MOS transistor 160, a current path from the power supply battery 110 to the ground potential via the relay circuit 120 is formed, and the relay circuit 120 is relay-connected to form a power feeding path to the electrical equipment.

  A protective resistance element R2 is connected to the gate terminal of the MOS transistor 160 toward the ground potential.

  The operation of the power supply control device 1 will be described with reference to FIG. When the ignition switch 130 is turned on by a key operation on the vehicle (period indicated by (ON) in FIG. 2), the power supply voltage from the power supply battery 110 is applied to one control terminal of the relay circuit 120 and one terminal of the momentary switch 140. Supplied. However, in this state, the momentary switch 140 is kept non-conductive, so that the power supply voltage is not applied to the power supply control device 1 and the other control terminal in the relay circuit 120 is also opened to form a current path. Not. Therefore, in the standby state in which the ignition switch 130 is turned on and waits for a power supply command to the electrical equipment, a current path from the power supply battery 110 is not formed and no dark current flows.

  Power supply to the electrical equipment is started by pressing the momentary switch 140. In response to the pressing of the momentary switch 140, the starting power supply capacitor C2 is charged to the power supply voltage of the power supply battery 110. During the subsequent pressing period, the charging voltage of the starting power supply capacitor C2 is maintained at the power supply voltage of the power supply battery 110. Further, a voltage VD1 substantially equal to the charging voltage VC2 of the starting power supply capacitor C2 is supplied to the power supply terminal of the T flip-flop circuit 150 via the diode D2 ((A) in FIG. 2).

  Here, the momentary switch 140 shown in FIG. 1 is a switch that conducts only during a pressing operation, and automatically returns to non-conducting after the operation. For example, a case where a vehicle user manually performs a switch operation is assumed. . However, the command input for power supply / non-power supply is not limited to a manual pressing operation, and it is conceivable that conduction control is performed according to a control signal from another control device or the like. After the pressing operation, the momentary switch 140 is turned off. The charging path to the starting power supply capacitor C2 is cut, and the charging voltage is discharged through the path from the resistance element R3 to the ground potential via the diode D1 and the resistance element R1.

  Charging voltage VC2 of starting power supply capacitor C2 further charges capacitor C1 via resistance element R3 and diode D1. The charging voltage VC1 of the capacitor C1 finally becomes a voltage value substantially equal to the charging voltage VC2 of the starting power supply capacitor C2, and is input as a command signal to the toggle input terminal of the T flip-flop 150. Here, the capacitor C1 is charged with a time constant determined by the resistance values of the resistance elements R1 and R3 and the capacitance value of the capacitor C1, and therefore, the capacitor C1 is delayed after charging the starting power supply capacitor C2.

  As a result, the charging voltage VC2 obtained by the charging operation of the starting power supply capacitor C2 is supplied as a power source for the T flip-flop circuit 150 and then input to the toggle input terminal as a command signal. In the T flip-flop circuit 150, a command signal can be input after a sufficient power supply voltage is supplied, and the command signal can be reliably stored.

  The diode D1 is provided to prevent chattering during the pressing operation of the momentary switch 140 from propagating to the toggle input terminal.

  When the charging voltage VC1 of the capacitor C1 becomes a high level and the signal level of the command signal transitions, the power supply control signal Q1 input to the T flip-flop circuit 150 as a toggle input and output from the output terminal Q is high. Invert to level. In response to the high-level power supply control signal Q1, the MOS transistor 160 is turned on to connect the relay circuit 120 to the relay, and power supply to the electrical equipment is started.

  When the power supply to the electrical equipment is started, the power supply from the power supply battery 110 is also supplied to the power supply path via the relay circuit 120. Therefore, the power supply is also supplied to the power supply terminal of the T flip-flop circuit 150 via the diode D3. Is performed ((B) in FIG. 2). The power supply source to the power supply terminal of the T flip-flop circuit 150 is switched from the starting power supply capacitor C2 ((A) in FIG. 2) to the power supply battery 110 ((B) in FIG. 2). The power is continuously supplied to the power supply terminal of the T flip-flop circuit 150, and the storage state of the command signal is maintained and the power supply state is maintained.

  To stop the power supply, the momentary switch 140 is pressed again. Similarly to the start of power supply, the startup power supply capacitor C2 is charged, and the capacitor C1 is also charged after a delay. After power is supplied to the T flip-flop circuit 150, a command signal is input, so that the power supply control signal Q1 is inverted to a low level. As a result, the MOS transistor 160 becomes non-conductive and the relay circuit 120 becomes non-conductive, and power supply to the electrical equipment is stopped. There is no power supply to the T flip-flop circuit 150 via the diode D3, and the power supply terminal of the T flip-flop circuit 150 is supplied from the starting power supply capacitor C2 via the diode D2 ((C )). The charging voltage VC2 of the starting power supply capacitor C2 is discharged through the resistors R3 and R1 and gradually decreases.

  A power supply control device 2 according to the second embodiment is shown in FIG. The path from the power supply battery 110 to the electrical equipment and the path from the momentary switch 140 are the same as those in the power supply control device 1 of the first embodiment, and a description thereof is omitted here.

  One terminal of the starting power supply capacitor C2 is connected from the momentary switch 140 through the resistance element R4. The other terminal of the starting power supply capacitor C2 is connected to the ground potential. A discharge path is formed between the terminals of the starting power supply capacitor C2 by a resistance element R5, which is an example of a discharge unit. The starting power supply capacitor C2 is connected to the input terminal of the hysteresis buffer circuit B and one input terminal of the OR gate OR1. The output terminal of the hysteresis buffer circuit B and the output terminal of the OR gate OR1 are connected to a set terminal and a reset terminal of a set-reset flip-flop circuit (hereinafter referred to as SR flip-flop circuit) FF2, respectively. The Q output terminal of the SR flip-flop circuit FF2 is connected to the other input terminal of the OR gate OR1. Command signal Q2 is output from the Q output terminal.

  The Q output terminal of the SR flip-flop circuit FF2 is further connected to the inverter gate INV1, and the output terminal of the inverter INV1 is connected to one input terminal of the NOR gate NOR1. Note that an OK signal OK indicating that the voltage value of a regulated voltage VD3 output from a regulator REG, which will be described later, is a predetermined value is input to the other input terminal. The output terminal of the NOR gate NOR1 is connected to the gate terminal of the MOS transistor M3. A power supply initial control signal OUT1 is output from the NOR gate NOR1. The MOS transistor M3 is controlled to supply the charging voltage VC2 of the starting power supply capacitor C2 to the gate terminal of the MOS transistor 160. The MOS transistor 160 is connected to the other control terminal of the relay circuit 120, and a current path from the power supply battery 110 to the ground potential through the relay circuit 120 is formed by conduction, and the relay circuit 120 is relay-connected to be electrically connected. A power supply path to the device is formed. A protective resistance element R6 is connected to the gate terminal of the MOS transistor 160 toward the ground potential.

  The hysteresis buffer circuit B, the OR gate OR1, the SR flip-flop circuit FF2, the inverter gate INV1, and the NOR gate NOR1 are supplied with power from the starting power supply capacitor C2.

  A power supply path from the power supply battery 110 to the electrical equipment is provided with a regulator REG that receives power supply during power supply. The regulated voltage VD3 output from the regulator is supplied as power to the storage unit 15 that is an example of a second storage unit that controls the power supply control circuit 2 to maintain the power supply state. A voltage is supplied to the drain terminal of the MOS transistor M2. The OK signal OK output from the regulator REG is input to the other input terminal of the NOR gate NOR1 and also input to the storage unit 15. The capacitor C3 is provided to stabilize the voltage level in the power supply path and to supply power to the regulator circuit REG for a predetermined period after the relay circuit 120 is disconnected.

  The storage unit 15 is a circuit that stores a command signal and outputs a power supply maintenance control signal Q3 after the relay circuit 120 is relay-connected and a power supply state to the electrical equipment is established.

  The AND gate AND1 is connected to the Q output terminal of the SR flip-flop circuit FF2, and receives the command signal Q2 and the OK signal OK. The output terminal of the AND gate AND1 is connected to one input terminal of the AND gate AND2 and to the delay circuit T1. The output terminal of the delay circuit T1 is connected to the other input terminal of the AND gate AND2 via the inverter gate INV2. The output terminal of the AND gate AND2 is connected to the toggle input terminal of the T flip-flop circuit FF3, and the Q output terminal is connected to the gate terminal of the MOS transistor M2. The MOS transistor M2 is controlled to supply the regulated voltage VD3 to the gate terminal of the MOS transistor 160.

  The operation of the power supply control device 2 will be described with reference to FIG. The operations of the ignition switch 130, the momentary switch 140, and the starting power supply capacitor C2 are the same as those in the first embodiment (FIGS. 1 and 2). If the momentary switch 140 remains non-conductive after the ignition switch 130 is turned on by a key operation on the vehicle, the power supply voltage is not applied to the power supply control device 2 and the ignition switch 130 is turned on. In a standby state waiting for a power supply command to the electrical equipment, a current path from the power supply battery 110 is not formed, and no dark current flows.

  The charging voltage VC2 of the starting power supply capacitor C2 is output to the set terminal of the SR flip-flop circuit FF2 after the voltage level is detected by the hysteresis buffer circuit B. Here, if the threshold voltage of the hysteresis buffer circuit B is set to be equal to or higher than a voltage value sufficient for the power supply voltage, the hysteresis buffer circuit is secured after a sufficient power supply voltage is secured in the circuit operating with the charging voltage VC2 as the power supply voltage. The output signal from the circuit B is inverted to a high level, and the SR flip-flop circuit FF2 is reliably set. That is, the high level command signal Q2 can be set reliably.

  The high level command signal Q2 is input to the initial power supply control unit 12 including the inverter gate INV1, the NOR gate NOR1, and the MOS transistor M3. After being inverted by the inverter gate INV1, the signal is inverted again by a NOR gate NOR1, which is an example of an inactive portion, and a power supply initial control signal OUT1 of a high level signal is output. As a result, the MOS transistor M3 is turned on to bias the gate terminal of the MOS transistor 160 with the charging voltage VC2 of the starting power supply capacitor C2, and the power supply to the electrical equipment is started by the connection of the relay circuit 120.

  When power supply to the electrical equipment is started, power from the power supply battery 110 is also supplied to the power supply path via the relay circuit 120, and power is supplied to the regulator circuit REG to start operation. When the regulated voltage VD3 output from the regulator REG rises and reaches a predetermined voltage level, a high-level OK signal OK is output. Thereby, the power supply to the storage unit 15 is sufficient, and the power supply control operation can shift from the initial operation to the steady operation. A high-level OK signal OK is input to the NOR gate NOR1 of the initial power supply control unit 12, and the power supply initial control signal OUT1 becomes low level.

  In combination with the above operation, the storage unit 15 starts the operation. When the command signal Q2 is maintained at the high level, the OK signal OK also transitions to the high level. Therefore, the high level trigger pulse signal T3 having the pulse width of the delay time of the delay circuit T1 is triggered by the high level transition. Is output from the AND gate AND2. In the T flip-flop circuit FF3 that has received the pulse signal T3, the power supply maintenance control signal Q3 output from the Q output terminal is inverted to a high level. As a result, the MOS transistor M2 becomes conductive, and the gate terminal of the MOS transistor 160 is biased by the regulated voltage VD3 instead of the charging voltage VC2. Before and after this, the MOS transistor 160 can maintain the conduction state, and the power feeding control can be shifted from the initial control state to the steady state.

  To stop the power supply, the momentary switch 140 is pressed again. Similarly to the start of power supply, the startup power supply capacitor C2 is charged, the SR flip-flop circuit FF2 is set again, and the command signal Q2 is set to the high level. The regulator circuit REG can be supplied with power for a predetermined period by the charging voltage to the capacitor C3, although the relay circuit 120 is disconnected and the power supply path is cut off. Since the regulated voltage VD3 is maintained and the OK signal OK is also maintained at a high level, the storage unit 15 generates a high-level trigger pulse signal T3. As a result, the power supply maintaining control signal Q3 is inverted to a low level and output from the Q output terminal of the T flip-flop circuit FF3. Since the MOS transistor M2 becomes non-conductive and the power supply initial control signal OUT1 output from the NOR gate NOR1 by the OK signal OK is maintained at the low level, the MOS transistor M3 is also maintained non-conductive. The gate terminal of the MOS transistor 160 is biased to a low level by the resistor element R6. The MOS transistor 160 becomes non-conductive, the relay circuit 120 is disconnected, and the power supply path is interrupted.

  A timing chart when the high-level trigger pulse signal T3 is output from the storage unit 15 is shown in FIG. When the output signal of the AND gate AND1 transitions to a high level, the signal delayed by the delay circuit T1 is inverted by the inverter gate INV2. By calculating the logical product of this signal and the output signal of the AND gate AND1 by the AND gate AND2, a high level trigger pulse signal T3 having the delay time of the delay circuit T1 as a pulse width can be obtained. The AND gates AND1 to AND2 of the initial power supply control unit 12 are examples of the trigger unit.

  In the power supply control device 1 (first embodiment) and the power supply control device 2 (second embodiment), capacitors, resistance elements, diodes, flip-flop circuits, gate circuits, and MOS transistors are integrated in a semiconductor integrated circuit device. Can be configured. In this case, as shown in FIG. 6, the MOS transistors M2 and M3 of the power supply control device 2 are preferably configured by integrated circuit components of the semiconductor integrated circuit device. In an individual semiconductor element (discrete component), the source terminal and the substrate terminal are often configured to have the same potential, and a so-called body diode is biased forward by a PN junction from the substrate to the drain terminal. is there. In contrast, in the MOS transistor of the integrated circuit component, the source terminal and the substrate terminal can be configured as separate terminals, and the body diode is not forward-biased.

  As described above in detail, according to the power supply control device 1 according to the first embodiment, the power supply terminal of the T flip-flop circuit 150 is connected to the charging voltage VC2 of the starting power supply capacitor C2 via the diode D2 in the initial stage of power supply. Is powered. After the power supply state is established, power is supplied from the power supply path via the diode D3. At this time, the charging voltage VC2 from the starting power supply capacitor C2 does not flow into the feeding path due to the rectifying action of the diode D3, and the charging voltage can be efficiently supplied to the power supply terminal. Further, due to the rectifying action of the diode D2, the power supply from the power supply path does not charge the starting power supply capacitor C2, and the command signal due to the charging of the starting power supply capacitor C2 is not erroneously output.

  Further, according to the power supply control device 2 according to the second embodiment, the initial power supply control unit 12 is supplied with power from the startup power supply capacitor C2, and outputs the power supply initial control signal OUT1 at the initial stage of power supply from the input of the command signal Q2. To do. After power supply to the electrical equipment is started, the storage unit 15 is supplied with power from the regulator circuit REG and outputs the command signal Q2 stored in the SR flip-flop circuit FF2 as the power supply maintenance control signal Q3.

  Here, the NOR gate NOR1 of the initial power supply control unit 12 generates the power supply initial control signal OUT1 based on the OK signal OK output from the regulator circuit REG activated in response to the start of power supply to the electrical equipment. Inactive.

  Further, the AND gates AND1 to AND2 of the storage unit 15 output the power supply maintenance control signal Q3 based on the output of the OK signal OK. After power is supplied to the power supply path and the power supply to the storage unit 15 is reliably performed, the trigger pulse signal T3 can be output to reliably store the command signal Q2.

  In addition, the resistor elements R1 and R3 and the capacitor C1 in the power supply control device 1 of the first embodiment, the hysteresis buffer circuit B, the OR gate OR1, and the SR flip-flop circuit FF2 in the power supply control device 2 of the second embodiment are signal transitions. It is an example of a delay part. The command signal can be output with a delay from the voltage transition of the charging voltage VC2 charged in the starting power supply capacitor C2, and the command signal can be reliably controlled.

  In the power supply control devices 1 and 2, the startup power supply capacitor C <b> 2 is charged in response to input of power supply and non-power supply commands, and power is supplied by the charging voltage VC <b> 2 of the capacitor C <b> 2 in the initial stage of power supply. After the power supply state is established, power is supplied from the power supply path, and the power supply state is maintained. When the electrical equipment is not used, power is not supplied to the power supply control devices 1 and 2, and the dark current flowing through the power supply control devices 1 and 2 can be eliminated. It is possible to reduce current consumption when the electrical equipment is not used.

  When power is supplied from the vehicle battery to the vehicle-mounted electrical device, power consumption from the vehicle battery can be reduced when the electrical device before power supply is not used, which can contribute to a longer battery life.

The present invention is not limited to the above-described embodiment, and it goes without saying that various improvements and modifications can be made without departing from the spirit of the present invention.
For example, in the present embodiment, the case where power is supplied from the vehicle battery to the in-vehicle electrical equipment has been described as an example, but the present invention is not limited to this. Any power supply system that supplies power to the electrical equipment from the power supply unit can be applied.

It is a circuit diagram of the electric power feeding control apparatus of 1st Embodiment. It is a timing chart of the electric power feeding control apparatus of 1st Embodiment. It is a circuit diagram of the electric power feeding control apparatus of 2nd Embodiment. It is a timing chart of the electric power feeding control apparatus of 2nd Embodiment. It is a timing chart which shows the production | generation of the trigger pulse signal in the memory | storage part of 2nd Embodiment. It is sectional drawing which shows the structure of a MOS transistor. It is a circuit diagram of the electric power feeding control apparatus of background art.

Explanation of symbols

1, 2 Power supply control device 12 Initial power supply control unit 15 Storage unit 110 Power supply battery 120 Relay circuit 130 Ignition switch 140 Momentary switch 150, FF3 T flip-flop circuit 160, M2, M3 MOS transistor B Hysteresis buffer circuit C2 Start-up power supply capacitor FF2 SR Flip-flop circuit M2 MOS transistor REG Regulator T1 Delay circuit OK OK signal OUT1 Power supply initial control signal Q1 Power supply control signal Q2 Command signal Q3 Power supply maintenance control signal T3 Trigger pulse signal VD3 Regulated voltage

Claims (8)

In the power supply control device, which is connected to the power supply unit, conducts according to the power supply and non-power supply commands to the electrical equipment, and includes a command switch unit that inputs a voltage signal from the power supply unit as a command signal.
A starting power supply capacitor for charging a voltage signal from the power supply unit via the command switch unit;
The power supply control device, wherein a charging voltage charged in the starting power supply capacitor is used as a power source in power supply initial control. A first storage unit that stores the command signal and outputs it as a power supply control signal;
A first rectifier connected between the starting power supply capacitor and a power supply terminal of the first storage unit and supplying power to the power supply terminal;
2. The power supply control according to claim 1, further comprising: a second rectification unit that is connected between a power supply path to the electrical equipment and a power supply terminal of the first storage unit and supplies power to the power supply terminal. apparatus. Using the charging voltage as a power source, in the initial stage of power feeding from the input of the command signal, an initial power feeding controller that outputs a power feeding initial control signal;
The power supply control device according to claim 1, further comprising: a second storage unit that is supplied with power based on the power supplied to the electrical equipment, stores the command signal, and outputs the command signal as a power supply maintenance control signal. The said initial electric power feeding control part is provided with the inactive part which deactivates the said electric power feeding initial control signal according to the power supply voltage value supplied based on the electric power feeding to the said electrical equipment. The power supply control device described. The said 2nd memory | storage part is provided with the trigger part which starts the memory | storage operation | movement of the said command signal according to the power supply voltage value supplied based on the electric power supplied to the said electrical equipment, The Claim 3 or 4 characterized by the above-mentioned. The power supply control device described. A signal transition delay unit that is connected to the start-up power supply capacitor in the input path of the command signal and outputs a signal with a voltage transition delayed as compared with the voltage transition of the charging voltage as the command signal; The power supply control device according to claim 2 or 3.   The power supply control device according to claim 1, further comprising: a discharge unit that discharges the charging voltage charged in the starting power supply capacitor after a predetermined time.   The power supply control device according to claim 1, wherein the power supply unit is a vehicle battery, and the electrical equipment is an in-vehicle electrical equipment.

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