JP2001025165A - Power supply unit for vehicle and intensively wired apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent abnormalities in short circuit in a power supply line in advance by discriminating whether a circuit breaker is turned on, based on an electric signal an abnormality detection means outputs if abnormality occurs in a load or a power semiconductor element. SOLUTION: A control signal from a control circuit 170 turns on and off a semiconductor switching element 115, to control the current passing through the coil of a relay 111 and turns on and off the contact of the relay 111. At this time, by preventing reverse-current from passing through the coil of the relay 111 with a diode 113, the contact of the relay 111 is turned off to shut down the current passage of a load and prevents a load from coming into action, even when a battery 3 is in opposite contact. As a result the relay 111 can be controlled if no power supply is made due to breakage of power bus, so that shutting down and connecting of a load power supply shutdown circuit 110a are conducted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle power supply device for supplying power from a power source mounted on a vehicle to a plurality of electric loads mounted on the vehicle, and more particularly to a power supply device suitable for an automobile. About.

[0002]

2. Description of the Related Art Vehicles are equipped with electric components as various electric loads. For example, in an automobile, a number of power supply wire harnesses are used to supply power to a number of electric loads from a power supply device such as a battery or a generator. When wiring a power supply line (wire harness) to an actual vehicle, the wiring harness is divided into areas such as the engine room, the room, the trunk room, and the door in consideration of wiring workability and repair work in case of failure. And a method of connecting with a connector. Accordingly, these wire harnesses partitioned by a plurality of connectors are supplied with electric power through several connectors from a power supply device such as a battery to an endless load.

In such a vehicle power supply system,
Generally, a single-sided ground power supply system, that is, a power supply system that uses a part of the vehicle body as one of the power supply paths from the power supply, is employed. )Become. Therefore, in a conventional vehicle power supply device, a fuse box is provided at a predetermined location of the vehicle, and a fuse (fusible piece) for overcurrent protection is provided from a power supply device for each predetermined load system. The protection is obtained by disconnecting from the power supply by blowing the fuse.

[0004] The fuses are collectively stored in a fuse box provided under a console box of an automobile or in a trunk room.

Therefore, in the prior art, depending on the load, a very long wire harness is connected to the power supply. If the power supply line is short-circuited, the rated current of the power supply line must be greater than the rated current of the fuse so that the power supply line does not smoke before the fuse is blown. ing. Further, even when the connection of the connector in the middle of the wire harness is loosened and the contact becomes poor, the power supply to the load becomes unstable. In addition, since the wiring harness is hidden inside the trim (interior) and wired, there is also a problem that it is difficult to specify a short-circuit abnormal position of the power supply line or a position where the connector is insufficiently fitted.

To solve such a problem, Japanese Patent Application Laid-Open No. 9-37482
Japanese Patent Application Laid-Open Publication No. H11-216555 proposes a power supply system in which a power protection element is connected in series with a power semiconductor element.

[0007]

However, in this conventional example, a load and a power semiconductor element (switching element) are not provided.
Protection is not enough. This is because a fuse is used as a power supply protection element, and it is necessary to replace the fuse when it is blown, resulting in poor workability. In addition, the operation (fusing) of the power supply protection element is given as its own eigenvalue,
Since it has no judgment ability, there is no flexibility in circuit design.

Another object of the present invention is to obtain a highly reliable power supply device that actively performs protection operation against a load abnormality (for example, short circuit).

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a load or power semiconductor element with an abnormality detecting means, and to provide a power supply and an electric load based on an electric signal output by the abnormality detecting means when the load or the power semiconductor element has an abnormality. This is achieved by determining whether or not to interrupt a circuit breaker (for example, a relay or a self-interrupting switch element) disposed on a power supply line between the power supply line and the power supply line.

[0010]

FIG. 1 is an overall view of an automobile system to which the present invention is applied, and shows an arrangement of parts constituting the present invention. Reference numeral 3 denotes a battery, which supplies power to the entire vehicle via a fusible link 4 disposed in the immediate vicinity of the battery. The powertrain control module (PCM) 10 controls the fuel injection amount and ignition timing of the engine, controls the throttle valve opening, and controls the engine transmission. It is mounted near the engine where the sensors and actuators for engine control are arranged (for example, the outer wall of the intake pipe, the outer wall of the surge tank, the inside of the air cleaner, etc.). The PCM 10 is connected to several sensors such as an air flow meter, a water temperature sensor, and a crank angle sensor, and an actuator group as an electric load such as an injector 9, an ignition device, and a throttle motor 35 for opening and closing a throttle valve. The control module 11 for the antilock brake system (ABS) is mounted behind the engine room adjacent to the actuator for the ABS. The air conditioner control unit (A / C) 16 is arranged near the dashboard on the passenger seat side near the installation location of the A / C temperature sensor and the actuator. The airbag control module (SDM) 25 is mounted near the center console box. The body control module (BCM) 14 is connected to a display device near the steering wheel, an ignition key switch 26, a hazard switch 27, a blinker switch, a wiper switch, and the like, and is installed near the dashboard. Each module has at least an arithmetic processing unit (CPU) and a communication circuit (communication IC) for performing data communication with other modules. Each module is installed near a device such as a sensor or an electric load connected to each module, thereby shortening a harness length between each module and a device connected thereto. FRONT IN
TEGRATION MODULE (FIM) 5 is for headlamps 1 and 6 and turn signal lamps 2a and 2b (left), 7a and 7b (right).
The head lamps 1, 6 and the turn signal lamps 2a, 2
b, 7a, 7b and a horn 8 mounted nearby are connected so as to be driven. DRIVER DOOR MODULE
(DDM) 18, PASSENGER DOOR MODULE (PDM) 20
Are mounted on doors on the driver's seat side and the passenger's seat side, respectively, and are connected to door lock motors 19 and 21, a power window motor, a door lock SW, a power window SW, an electric mirror motor (not shown), and the like. ing. RE
The AR INTEGRATION MODULE (RIM) 29 is disposed in front of the trunk room adjacent to the tail lamps 32 and 33 and the turn signal lamps 31 and 34, and is used for a trunk opener in addition to the tail lamps 32 and 33 and the turn signal lamps 31 and 34. Motors, rear defoggers, rear door lock motors 23 and 28, a power window motor, a door lock SW, a power window SW, and the like are connected so as to be driven. The FIM5 and RIM2
9, the DDM 18, and the PDM 20 each have a communication circuit for exchanging data with another module. Also, an input / output interface to which devices such as sensors, switches, and external electric loads are connected, and an arithmetic processing unit (CP) for calculating control signals to the electric loads.
U).

In order to transfer data between the modules, a multiplex communication line 30 connects the communication circuits of the modules. In this way, since each module is arranged close to the device to be connected, and the input data and output data of the device not connected to itself are transmitted to and received from other modules via the multiplex communication line, The necessary data for each module can be obtained. The multiplex communication line 30 can be connected to the diagnostic device 13 via the connector 35, and the diagnostic device 13 can obtain information necessary for diagnosis from each module via the communication line.

A power supply line from the battery 3 is connected to the FIM 5 via the fusible link 4 and the FIM 5
Power supply line 12A, connector 17A, power supply line 12B
Through the power line 12 between the BCM 14 and the RIM 29.
C, the connector 17B, and the power supply line 12D, the RIM2
9 to the BCM 14, a power line 12E, a connector 17C,
The power supply line 12F connects the BCM 14 to the FIM 5 via a power supply line 12G, a connector 17D, and a power supply line 12H, and is wired in a loop in the vehicle. In this way, the power supply line is wired in a loop in the vehicle, and each module is connected to the power supply line wired in the loop or the power supply line is connected to each module. Power to various actuators. Each module is configured such that one module is arranged in each of the engine room, the vehicle interior, and the trunk room (in the present embodiment, each module is configured by FIM, BCM, and RIM). According to the configuration of the embodiment, the impedance of the power line in each control unit is equivalently connected in parallel, and the power system can be configured using a power supply line with a small rated current. Module DD placed on the door
Power is supplied from the BCM 14 to the M18 and the PDM 20.

The power lines arranged in a loop can be detached by connectors 17A, 17B, 17C and 17D. The power lines 12A and 12H are connected to the engine room, the power lines 12B, 12C, and the power lines. The line 12F and the power line 12G can be separated from each other such as a vehicle cabin, and the power line 12D and the power line 12E can be separated into a trunk room.

Therefore, the power supply line can connect and connect not only the loop shape but also the control module in a star shape or a tree shape. For example, if the power supply lines 12H, 12F, 12G, and 12H connected by the connectors 17D and 17C are removed, a tree connection is obtained.

Next, an embodiment to which the power supply system of the loop connection shown in FIG. 1 is applied will be described with reference to FIG. First, the configuration of the embodiment of FIG. 2 will be described. The power supply line wired in a loop described with reference to FIG. 1 is connected to the load power cutoff circuit 110 of the FIM 5 from the battery 3 via the fusible links 4f and 4e.
Connected to. The power supply from the fusible link 4f is connected to the power supply line 12A via the load power supply cutoff circuit 110. The power line 12A is connected to the power line 12 by the connector 17A.
B is connected to one end, and the other end is connected to a load-side power cutoff circuit 210 of the BCM 14 to a BCM module-side connector described later. The power supply line 12B is electrically connected to a power supply line 12C having one end connected to a module-side connector of a BCM, which will be described later, via a load power supply cutoff circuit 210.
The other end of 2C is connected to one end of the power supply line 12D by a connector 17B, and is connected to a load power cutoff circuit 310 of the RIM 29 via a RIM module-side connector described later.
The other end of the power supply line 12D is the load power supply cutoff circuit 3 of the RIM 29.
10, and is electrically connected to a power supply line 12E having one end connected to a module-side connector of a RIM described later,
The other end of the power line 12E is connected to the power line 12F by the connector 17C.
And the other end of the power supply line 12F is connected to the load power cutoff circuit 210 of the BCM 14. The other end of the power supply line 12F is electrically connected to one end of a power supply line 12G via a load power supply cutoff circuit 210 of the BCM 14 via a BCM module-side connector described later, and the other end of the power supply line 12G is connected to a connector. The power supply line 12H is connected at 17D to one end of the power supply line 12H, and the other end is connected to the load power supply cutoff circuit 110 of the FIM 5 via a FIM module side connector described later.
On the other hand, the power supply from the fusible link 4e is the module F
The power supply line 12H is electrically connected to the other end of the power supply line 12H through a module side connector to be described later via the load power supply cutoff circuit 110 of the IM5.
Are wired in a loop through the fuses 4e and 4f. The power supply lines arranged in a loop are collectively referred to as a power bus 12 hereinafter.

The power supply lines 12A, 12B, 12C, 12
One example of the structure of D, 12E, 12F, 12G, and 12H is, as shown in FIG. 26, a power supply line 3020 as a center, an insulating material 3030 covering the periphery thereof, a conductor 3010 covering the outer periphery of the insulating material 3030, Further, an insulating material 3000 covering the outer periphery of the conductor 3010 is provided. Here, first, the power supply line 3020 is usually made of a single copper wire or a stranded wire, and serves as a conductive wire for supplying power. The insulating material 3030 is made of an insulator such as rubber or plastic, and functions to insulate the power line 3020. Conductor 30
Reference numeral 10 denotes a layer formed on the outer periphery of the insulating material 3030 by knitting a thin copper wire (hereinafter referred to as a braided wire). The insulating material 3000 is made of an insulator such as rubber or plastic, and functions as a protective layer of the cable. Although the function of the conductor 3010 will be described in detail later, the power supply line 12A
One end of the conductor 3010 is connected to the short detection circuit 230 of the FIM 5, and the other end is in the open state immediately near the connector 17A. Similarly, the conductor 3 of the power supply line 12B
One end of 010 is a short detection circuit 230 of BCM14.
One end of the conductor 3010 of the power supply line 12C is connected to the BCM 14
Is connected to the conductor 3 of the power supply line 12D.
One end of 010 is connected to the short detection circuit 330 of the RIM 29,
One end of the conductor 3010 of the power supply line 12E is connected to the short detection circuit 330 of the RIM 29 and the conductor 3010 of the power supply line 12F.
Is connected to the short detection circuit 230 of the BCM 14, one end of the conductor 3010 of the power line 12G is connected to the short detection circuit 230 of the BCM 14, and one end of the conductor 3010 of the power line 12H is connected to the short detection circuit 130 of the FIM5. , All power supply lines 12B, 12C, 12D, 12E,
The other ends of 12F, 12G, and 12H are open in the immediate vicinity of the respective connectors. This conductor 3010 is hereinafter referred to as a short sensor. On the other hand, the power supply line 3020 starts from the FIM 5 as described above, and starts from the power supply line 12A, the connector 17A, the power supply line 12B, the BCM 14, the power supply line 12C,
Connector 17B, power supply line 12D, RIM29, power supply line 1
2E, connector 17C, power supply line 12F, BCM 14, power supply line 12G, connector 17D, power supply line 12H,
It is connected in a loop to return to FIM5.

The power line 1 wired in a loop as described above
2A to 12H are connected to the respective modules via the load power cutoff circuits 110, 210, 310 of the FIM5, BCM14, RIM29 and the respective load drive circuits (driver circuits) 160, 260, 360 of the modules FIM5, BCM14, RIM29. Electrical loads 190, 2
90, 390. Another module D
The DM 18 and the PDM 20 are one of the power supply lines connected to the load power supply cutoff circuit 210 of the BCM 14 on the side closer to the power supply.
Electric power is supplied from 2B and 12G via the power supply circuit 200. A / C16, SDM25, radio 15
Power supply circuit 200 of BCM 14 via power supply line 50f
Supplies backup power.

The battery 3 is provided separately from the load power supply line described above.
From FIM5, BCM14, RIM
29. From the battery 3 via the fuse 4b to the control system power supply circuit 120 of the FIM 5, to the control system power supply circuit 220 of the BCM 14 via the fuse 4c, and to the control system power supply circuit 320 of the RIM 29 via the fuse 4d. Power is supplied. In this way, by supplying power to the control system by another system, even if one of the modules fails, the other modules can operate.

The power bus 12 controls head lamps, stop lamps, warning lamps, power windows, door locks, etc., and supplies power to an electric load called a so-called body electric system or outfitting system. An engine control module (ECM) that controls an injector that controls the fuel injection amount of the engine, an ignition device that controls the ignition timing, a motor that controls the throttle valve opening, an automatic transmission (ATM) that controls the engine transmission, Powertrain control module (PCM) for powertrain system
From the battery 3 via the fusible link 4a, the ignition switch 26a, the fuse 36b in the fuse box 36 disposed near the dashboard, and the power supply line 50b. Power is being supplied by the grid. Power is supplied to the ABS control unit 11 via the fusible link 4a, the ignition switch 26a, the fuse 36a in the fuse box 36, and the power supply line 50a. Airbag control unit SDM
25 includes a fusible link 4a, an ignition switch 26a, and a fuse 36 in a fuse box 36.
c and the power supply line 50c. Power is supplied to the radio 15 via the fusible link 4a, the accessory switch 26b, the fuse 36d in the fuse box 36, and the power supply line 50d. The A / C unit 16 includes a fusible link 4a, an accessory switch 26b, a fuse box 3
Electric power is supplied from the battery 3 via the fuse 36e in 6. As described above, since each control system having a different function is set as a separate power supply system,
Even if one power supply system fails, the other power supply systems are not affected.

The BCM 14 has a power supply circuit 200,
The power supply circuit 200 is connected to the power lines 12B and 12G via power lines 210b and 210g. Since power is supplied to the radio 15, the SDM 25, and the A / C 16 via the accessory switch 26b or the ignition switch 26a, no power is supplied when the accessory switch 26b or the ignition switch 26a is turned off. At that time, in order to back up the data during operation, it is necessary to supply power even when the ignition switch 26a and the accessory switch 26b are turned off. Therefore, power for backing up data of these modules is supplied from the power supply circuit 200 of the BCM 14 via the power supply 50f. Since the power supply for data backup is obtained from the power bus 12, there is no need to provide another power supply line and fuse for data backup. Also,
Even if the power bus systems 12A to 12H break down and the backup data is deleted, the radio 15, SDM2
5, if the A / C 16 is configured to start operating at an initial value when power is supplied via the accessory switch 26b and the ignition switch 26a, a fatal failure does not occur.

Body electrical module FIM5, BC
M14, RIM29, DDM18, and PDM20 have communication circuits 140, 240, 340, 640, and 540, respectively.
Connected by Each module is, for example, B
By mutually transmitting and receiving input / output information relating to the entire vehicle such as the state of an ignition key switch input to the CM 14, a drive provided in another module is driven and controlled by an input signal taken in one module. it can.

Power is supplied to the DDM 18 and the PDM 20 via a power supply circuit 200 of the BCM 14. Therefore, the power supply circuit 520 of the DDM 18 and the power supply circuit 62 of the PDM
0 is connected to the power supply circuit 200 of the BCM 14 via the power supply lines 23 and 24, respectively.

The load group 290 connected to the BCM 14 receives power supply via an output circuit (driver circuit) 260.

The output circuit 260 is connected to power supplies 12c and 12f via power supply lines 210c and 210f.

The output circuit 260 receives a control signal from the control signal output line group 270b of the control circuit 270 and controls the driving of the load.

The control circuit 270 outputs a load control signal to the output circuit 260 based on the input signal 280, the ignition switch signal, the accessory switch signal, and the reception signal input from the input interface of the input circuit 250 and the communication circuit 240.

The BCM module 14 has a short-circuit detection circuit 230, and monitors a short-circuit abnormality of the power supply lines 12B, 12C, 12F, and 12G. Short detection circuit 230
When, for example, a short-circuit abnormality of the power supply line 12F is detected, the signal is input to the control circuit 270, and the output signal line
The load power supply cutoff circuit 210 is driven via 70a, and one end of the power supply line section 12F having the short-circuit abnormality is connected and separated. At this time, the control circuit 270 transmits, via the communication circuit 240, a signal for specifying the power supply line section having the short-circuit abnormality to another module. A predetermined module RIM 29 receiving this
Is connected via its own control circuit 370 to disconnect the power supply line 12E involved in the short circuit abnormality.
Control 0. As a result, the short-circuit abnormal section 12F
Then, the power supply line 12E connected to the 12F via the connector 17C is disconnected from the loop-shaped power supply line, and thereafter the trunk line composed of the power supply lines 12A, 12B, 12C and 12D and the power supply circuit 200 Power is supplied to each load by a tree connection composed of the technique lines 23, 24, and 50f wired from.

The FIM module 5 has a short-circuit detection circuit 130 and monitors a short-circuit abnormality of the power lines 12A and 12H. When the short-circuit detection circuit 130 detects, for example, a short-circuit abnormality of the power supply line 12A, the signal is input to the control circuit 170, the load power supply cut-off circuit 110 is driven via the output signal line 170a, and the short-circuit abnormality power supply line section 12A Are separated from each other. At this time, the control circuit 1
Reference numeral 70 transmits a signal specifying a power supply line section having a short-circuit abnormality to another module via the communication circuit 140. The control circuit of the BCM module 14 receiving this outputs the output signal line 2
The load power supply cutoff circuit 210 is driven via 70a, and the other end of the power supply line 12B connected to the power supply line 12A via the connector 17A is opened.

In this state, each module includes a battery 3, a fuse 4e, a load power supply cutoff circuit 110 of the FIM module 5, power supply lines 12H and 12G, a load cutoff circuit 210 of the BCM module 14, and power supply lines 12F, 12E, R
Power is supplied to the load by a tree connection including the trunk line including the load cutoff circuit 310 of the IM module 29 and the technical lines 23, 24, and 50f wired from the power supply circuit 200 of the BCM module 14.

FIGS. 3, 4, 5, 6, and 7 are block diagrams of the module of the embodiment of FIG. The notation of the semiconductor switching element written in the drawings of the present specification is as follows:
For convenience of explanation, a symbol representing a transistor generally represents a semiconductor switching element having no short-circuit protection function, and a symbol representing a MOSFET represents a semiconductor switching element having a short-circuit protection function. The configuration of the FIM 5 will be described with reference to FIG. The load power cutoff circuit 110 of FIG.
Of the load power supply cutoff circuit 110b. The first load power cutoff circuit 110a includes a relay 111 and a diode 11
3. It is composed of a semiconductor switching element 115.
The second load power supply cutoff circuit 110b is the same as the first load power supply cutoff circuit 110a, and includes a relay 112, a diode 114, and a semiconductor switching element 116. The relays 111 and 112 use relays whose contacts are turned on when a current flows through the coil and turned off when the current is cut off. About operation and detailed configuration
Since the second load power cutoff circuits 110a and 110b are the same, only the first load power cutoff circuit 110a will be described. By turning on and off the semiconductor switching element 115 by a control signal from the control circuit 170, the current flowing through the coil of the relay 111 is controlled, and the contact of the relay 111 is turned on and off. Without the diode 113, when the battery 3 is connected in reverse, a reverse current flows through the coil of the relay 111, and the contact of the relay 111 turns on irrespective of the control signal. However, the reverse current is prevented from flowing through the coil of the relay 111 by the diode 113, and the contact of the relay 111 is turned off. Thus, the diode 113
, Even if the battery 3 is reversely connected,
Since the relay is turned off, the current path of the load is interrupted, and a malfunction such that the load continues to operate can be prevented. Relay 1
The power supply to the coil 11 is connected to the power supply of the control system described in FIG. 2, one end of the contact of the relay 111 is connected to the battery 3 via the fusible link 4f, and the other end is connected to the loop system power supply. An output circuit 16 connected to the power supply line 12A of the supply system and for supplying power to the load at the same time.
Connected to 0. As described above, the power supply to the coil of the relay 111 is performed from the control system power supply, and the power supply to the control circuit 170 that outputs the control signal of the coil is also performed from the control system power supply. Even if power is not supplied, the relay 111 is controlled,
The first load power supply cutoff circuit 110a can be cut off and connected. Further, when it is not necessary to operate the load and it is desired to reduce the current, the current supplied to the relay 111 can be cut off to cut off the power supplied to the load, so that the current consumption can be reduced. Conversely, if the control system power supply fails,
The current to the relay 111 is cut off and the load power cutoff circuit 1
Since the power supply 10a is shut off and power is not supplied to the load, even if the control circuit malfunctions, all the loads are stopped and no malfunction occurs.

The output circuit 160 includes an overcurrent detection circuit 16
1, 162 and semiconductor switching elements 163 to 168 for supplying power to the load and controlling the driving. In this embodiment, the semiconductor switching elements 163 to 163
Power MOSFET with built-in over temperature detection cutoff function
When an overcurrent flows and the temperature of the element becomes equal to or higher than a predetermined temperature, the element is turned off. Therefore, even if the load is short-circuited, the current does not continue to flow, and the harness does not smoke, the fuse does not blow, and the battery is not over-discharged. Semiconductor switching elements
Although only six are shown in the figure, the number naturally increases or decreases according to the load connected to the FIM 5. Semiconductor switching element 1
63, 164, 165 are respectively connected to a washer motor 191, a turn lamp right 7a, and a head lamp right 6 which are arranged on the right side of the vehicle with a load 190 connected to the FIM 5, and the semiconductor switching elements 166, 167, 16
8, a horn 8 arranged on the left side of the vehicle with a load 190 connected to the FIM 5, a turn lamp left 2a,
Headlamp left 1 is connected. The other ends of the semiconductor switching elements 163, 164, and 165 are connected to the overcurrent detection circuit 161. The other end on the upstream side of the overcurrent detection circuit 161 is supplied with power from the second load power supply cutoff circuit 110b. I have. Semiconductor switching elements 166, 16
The other ends of the circuits 7 and 168 are connected to an overcurrent detection circuit 162, and the other end upstream of the overcurrent detection circuit 162 is supplied with power from a first load power supply cutoff circuit 110a. As described above, the right and left sides of the vehicle are provided as separate systems, and even if one of the systems fails, another system operates. Here, the reason why the right and left sides of the vehicle are separated from each other is
This is because a large number of loads, such as headlamps, fog lamps, and clearance lamps, which are paired on the left and right, are connected to the FIM5. For example, if the headlamp left 1 and the headlamp right 6 are powered by the same power supply system, if the overcurrent detection circuit of the power supply system fails and power is not supplied, both the left and right headlights are turned off. It is very dangerous during night driving. If the right and left sides of the vehicle are separated from each other as in this embodiment, the worst situation can be avoided because either of them is lit.

The control system power supply circuit 120 includes the diode 12
2, a constant voltage power supply circuit 121 and a power supply cutoff circuit 123. The control system power supplied from the battery 3 via the fuse 4b is supplied to the constant voltage power circuit 121 via the diode 122. The constant voltage power supply circuit 121 generates a constant voltage for operating a control circuit 170 for performing various arithmetic and control processes. This voltage is supplied to the voltage application drive circuit 131 of the short detection circuit 130, the control circuit 170, the communication circuit 140, and the power cutoff circuit 123. The power cutoff circuit 123 supplies or cuts off the constant voltage power supplied from the constant voltage power supply circuit 121 to the input circuit 150 according to the control signal of the control circuit 170. The input circuit 150 detects the outside temperature sensor 1 of the input signal 180.
Signals from the controller 81 and the brake fluid level sensor 182 are converted into voltages that can be taken by the control circuit 170. For this purpose, pull-up is performed by resistors 151 and 152. However, when there is no person in the vehicle and the vehicle is left unattended, the brake fluid level sensor 182 and the outside air temperature sensor 18
When the current flows through the brake fluid level sensor 182 and the outside air temperature sensor 181 via the pull-up resistors 151 and 152, though there is no need to issue an alarm or the like based on the information of the battery 1, the battery 3 is discharged and the battery 3 is discharged. Will go up. Therefore, when it is not necessary, the power supplied to the pull-up resistor is cut off by the power cutoff circuit 123.

The short detection circuit 130 comprises a voltage application drive circuit 131, pull-up resistors 132 and 135, and pull-down resistors 133 and 134 to the ground.
The voltage application drive circuit 131 turns on and off the power supply to the pull-up resistors 132 and 135 according to the control signal of the control circuit 170. The other end of the pull-up resistor 132 and the other end of the pull-down resistor 133 are connected to the outside of the FIM 5 via a connector for connection to the outside of the FIM 5, and the power line 1
Connected to 2H short sensor. Also FIM5
Is input to the control circuit 170. Similarly, the other ends of the pull-up resistor 135 and the pull-down resistor 134 are connected to the FIM 5
5 and connected to the short sensor of the power supply line 12A. Further, the signal is input to the control circuit 170 inside the FIM 5. Thus, pull-up resistor 1
The reason why the 35 and the other end of the pull-down resistor 134 are connected outside the FIM 5 via a connector for connection to the outside of the FIM 5 is as follows. Since the other end of the short sensor is open as described above,
Normally, no current flows to the short sensor. Then, since no current flows through the connector, the contact portion may be oxidized and a contact failure may occur. Therefore, when the configuration as in this embodiment is adopted, the pull-up resistors 135 and 135 are connected to the connector.
Since current flows through the path of the two connection connectors and the pull-down resistor 134, oxidation can be prevented.

FIG. 4 is a block diagram of the BCM 14. The first load power cutoff circuit 210a and the second load power cutoff circuit 210b of FIG. 2 have the same configuration as the first load power cutoff circuit 110a and the second load power cutoff circuit 110b of the FIM 5 of FIG. However, the power supply to the coil of relay 211 is
2, one end of a contact point of the relay 211 is connected to the power supply line 12B of the loop power supply system, and the other end is connected to the power supply line 12C of the loop power supply system.
At the same time, both ends are connected to a power supply circuit 200 or an output circuit 260 for supplying power to the load. Output circuit 260 and power supply circuit 200
Has a different name but the same function and configuration,
It will be explained at the same time. Overcurrent detection circuits 261, 262, 20
1,202 and semiconductor switching elements 263 to 266,203,2 for supplying power to the load and controlling the driving.
04. In this embodiment, a power MOSFET having a built-in over-temperature detection / shutoff function is used for the semiconductor switching elements 263 to 266, 203, and 204. Has become. Therefore, even if the load is short-circuited, the current does not continue to flow, and the harness does not smoke, the fuse does not blow, and the battery is not over-discharged. Although only six semiconductor switching elements are shown in the figure, the number of the semiconductor switching elements naturally increases or decreases according to the load connected to the BCM 14. The semiconductor switching elements 263 and 264 are connected to room lamps 293 and 294 of the load 290 connected to the BCM 14, respectively, and the semiconductor switching elements 265 and 266 are respectively connected to the instrument panel of the load 290 connected to the BCM 14. Are connected to the semiconductor switching element 203, the DDM 18 arranged at the driver's seat door, and the semiconductor switching element 204 are connected to the PDM 20 arranged at the passenger's seat door. ing. The other ends of the semiconductor switching elements 263 and 264 are connected to an overcurrent detection circuit 261,
The power supply of the second load power supply cut-off circuit 210b is supplied from the power supply line 12F to the other end on the upstream side. The other ends of the semiconductor switching elements 265 and 266 are connected to an overcurrent detection circuit 262, and the other end upstream of the overcurrent detection circuit 262 is connected to the first load power supply cutoff circuit 21 from the power line 12C.
0a is supplied. The other end of the semiconductor switching element 203 is connected to the overcurrent detection circuit 201, and the other end on the upstream side of the overcurrent detection circuit 201 is supplied with power of the second load power cutoff circuit 210b from the power supply line 12G. I have. The other end of the semiconductor switching element 204 is connected to the overcurrent detection circuit 202, and the other end upstream of the overcurrent detection circuit 202 is supplied with power of the first load power supply cutoff circuit 210a from the power supply line 12B. I have. in this way,
The front right side and the front left side, the rear right side, and the rear left side in the vehicle compartment are separate systems, and even if one of the systems fails, another system operates.

The control system power supply circuit 220 is the FIM5 of FIG.
The configuration and operation are the same as those of the control system power supply circuit 120.
The input circuit 250 includes an intermittent wiper volume 282, a wiper switch 283, and a light switch 28 for an input signal 280.
1, ignition key switch (not shown in FIG. 4)
Signals from such devices are converted into voltages that can be captured by the control circuit 270. Therefore, the resistors 251, 252, 2
Pulled up at 53. Intermittent wiper volume 28
2 and the load controlled by the input signal of the wiper switch 283 always operate only when the ignition switch is turned on. Therefore, when there is no person in the vehicle and the vehicle is left, it is not necessary to take in the input information. The power supplied to the pull-up resistors 251, 252 is cut off by the power cut-off circuit 123. on the other hand,
The light switch 281, the ignition switch, and the like may be turned on suddenly when the vehicle is left unattended and unattended, so that the load must be driven. It is necessary to always detect the input state even when it is running. Therefore, the power supply of the pull-up resistor 253 is always connected to the output of the constant voltage power supply circuit 221 to which the power is supplied.

The short detection circuit 230 is connected to the power line 12
B, power supply line 12C, power supply line 12F, and power supply line 12G.

FIG. 5 is a block diagram of the RIM 29. The load power cutoff circuit 310 has the same configuration as that of the first load power cutoff circuit 110a of the FIM 5 in FIG. One end of the contact point of the relay 311 is connected to the power supply line 12D of the loop power supply system, and the other end is connected to the power supply line 12E of the loop power supply system. Is connected to the output circuit 360.

The output circuit 360 is connected to the overcurrent detection circuit 36.
1 and 362 and semiconductor switching elements 364 to 368 for supplying power to the load and controlling the driving. In this embodiment, the semiconductor switching element 364,
Each of 365, 367 and 368 uses a power MOSFET having a built-in function for detecting and shutting off an over-temperature, and is turned off when an overcurrent flows and the temperature of the element becomes higher than a predetermined temperature. Therefore, even if the load is short-circuited, the current does not continue to flow, and the harness does not smoke, the fuse does not blow, and the battery is not over-discharged. Although only six semiconductor switching elements are shown in the figure, it naturally increases or decreases according to the load connected to the RIM 29. The semiconductor switching elements 363, 364, 365 are connected to a power window motor 391 of the rear right door of the load 390 connected to the RIM 29, a fuel pump 392 arranged on the right side of the trunk room, a stop lamp right 393, and the like. Switching elements 366, 36
7, 368 have loads 39 connected to the RIM 29, respectively.
0, power window motor 394 at the rear left door, trunk room lamp 3 arranged on the left side of the trunk room
95, stop lamp left 396, and the like.
The other ends of the semiconductor switching elements 363, 364, and 365 are connected to the overcurrent detection circuit 361, and the other end on the upstream side of the overcurrent detection circuit 361 is supplied with power of the load power supply cutoff circuit 310 from the power supply line 12E. Have been. The other ends of the semiconductor switching elements 366, 367, and 368 are connected to an overcurrent detection circuit 362, and the other end upstream of the overcurrent detection circuit 362 is supplied with power of the load power supply cutoff circuit 310 from the power supply line 12D. ing. As described above, the right and left sides of the vehicle are provided as separate systems, and even if one of the systems fails, another system operates. Here, the reason why the right and left sides of the vehicle are separated from each other is that many load pairs, such as stop lamps and tail lamps, are connected to the RIM 29 on the right and left sides. For example, if the stop lamp left 396 and the stop lamp right 393 are powered by the same power supply system, if the overcurrent detection circuit of the power supply system fails and power is not supplied, both the left and right stop lamps are turned off. It is very dangerous because it does not light when braking. If the right and left sides of the vehicle are separated from each other as in this embodiment, the worst situation can be avoided because either of them is lit. The semiconductor switching elements 363 and 366 are H-bridge circuits that drive the motor in both forward and reverse directions, and the configuration will be described later.

The control system power supply circuit 320 is the FIM5 of FIG.
The configuration and operation are the same as those of the control system power supply circuit 120.
The input circuit 350 is a door open / close switch 3 for the input signal 380.
Signals from the power window switch 82 and the power window switch 383 on the rear seat are converted into voltages that can be taken in by the control circuit 370. For this purpose, the pull-up is performed by the resistors 351 and 352. These switches are used when the vehicle is empty
Since it is not necessary to take in input information when left unattended, the power supplied to the pull-up resistors 351 and 352 is cut off by the power cutoff circuit 323.

The short detection circuit 330 is connected to the power line 12
D, and two short sensors of the power supply line 12E.

FIG. 6 shows a configuration of the PCM 10 supplied with power in a system different from the loop power supply system. 2 includes a power supply circuit 720, a control circuit 770, an input circuit 750, and an output circuit 760. The power supply circuit 720 includes a diode 722 and a constant voltage power supply circuit 72.
It is composed of 1. The power supplied from the battery 3 via the fuse 4a, the ignition switch 26a, and the fuse 36b is supplied to the constant voltage power supply circuit 721 via the diode 722, while the semiconductor of the output circuit 760 serves as a load driving power supply. Switching elements 761, 7
65. In the constant voltage power supply circuit 721,
A constant voltage for operating a control circuit 770 for performing various arithmetic and control processes is generated. The input circuit 750 converts a signal of the input signal 780 from the crank angle sensor 781, the air flow sensor 782, the throttle sensor 783, and the like into a voltage that can be taken by the control circuit 770.

The output circuit 760 is a semiconductor switching element 761 for supplying power to a load and controlling driving.
And 765, and semiconductor switching elements 762, 763, and 765 for turning on and off the load. In this embodiment, the semiconductor switching element 765 uses a power MOSFET having a built-in over-temperature detection cutoff function.
When an overcurrent flows and the temperature of the element becomes equal to or higher than a predetermined temperature, the element is turned off. Therefore, even if the load is short-circuited, the current does not continue to flow, and the harness emits smoke,
There is no blown fuse or over-discharged battery. On the other hand, the semiconductor switching elements 762 and 76
3,765 uses a simple semiconductor switching element having no protection function. This is because, even if a load or the like is short-circuited and an overcurrent flows, a fuse located upstream of the load is blown and the overcurrent does not continue to flow. Although a semiconductor switching element having no protection function is used in this embodiment, it goes without saying that there is no problem if a semiconductor switching element having a protection function is used. Although only five semiconductor switching elements are shown in the figure,
Naturally, it increases or decreases according to the load connected to the PCM 10. The semiconductor switching elements 762, 763, and 764 are connected to a warning lamp 792, an injector 793, and an EGR solenoid 794 of a load 790 connected to the PCM 10, respectively. Fuses 36f, 36g, and 36h are connected upstream of these loads. Have been. An AT solenoid 791 of a load 790 connected to the PCM 10 and the like are connected to the semiconductor switching element 761. The semiconductor switching element 765 is an H-bridge circuit that drives the throttle motor 795 in both forward and reverse rotations, and its configuration will be described later.

Similarly to the PCM 10, the ABS 11 and the A / C 1 shown in FIG.
6, SDM 25, and radio 15 are also configured as PCM1 in FIG.
Since the configuration is almost the same as that of the module 0, the description is omitted, but the input signal and the load connected to the module are different.

FIG. 7 shows a power supply circuit 200 of the BCM 14.
This is the configuration of the DDM 18 supplied with power from the. DDM1
8 is a power supply circuit 620, a control circuit 670, and an input circuit 65.
0, output circuit 660, communication circuit 640, input signal 680
And part of the load 690. The power supply circuit 620 includes a constant voltage power supply circuit 621 and a power supply cutoff circuit 623. The power supplied from the power supply circuit 200 of the BCM 14 is supplied to the constant voltage power supply circuit 721 and also supplied to the switching elements 663, 664, 665 and the load 691 of the output circuit 660 as power for driving the load. I have. The constant voltage power supply circuit 621 generates a constant voltage for operating a control circuit 670 for performing various arithmetic and control processes. The input circuit 650 receives the input signal 68
The signal from the power window switch 681 and the door lock switch 682 incorporated in the module No. 0 is converted into a voltage that can be taken by the control circuit 370.
For this purpose, pull-up is performed by resistors 651 and 652.
Since these switches do not need to take in input information when the vehicle is left unattended and unattended, the power supplied to the pull-up resistors 651 and 652 is cut off by the power cutoff circuit 623. ing.

The output circuit 660 includes switching elements 663 and 66 for supplying power to the load and controlling driving.
4, 665, and semiconductor switching elements 661, 662 for turning on and off the load. In this embodiment, a simple semiconductor switching element having no protection function is used for the semiconductor switching elements 661 and 662. This is because even if the load is short-circuited and an overcurrent flows, the power supply circuit 2 of the BCM 14 located upstream of the load
This is because the overcurrent does not continue to flow because 00 has a protection function. Although a semiconductor switching element having no protection function is used in this embodiment, it goes without saying that there is no problem if a semiconductor switching element having a protection function is used. As the switching elements 663, 664, 665 for driving the power window motor 693, the door lock motor 694, and the mirror motor 695, relays are used, but semiconductor switching elements may be used. The semiconductor switching element 661 has a load 6 built in the DDM 18.
90, a switch illumination lamp 691 is connected, and a semiconductor switching element 662 is connected to a step lamp 692 installed on a door.
The power supply circuit 200 of the CM 14 is connected.

The configuration of the PDM 20 is almost the same as the configuration of the DDM 18 in FIG.

As described above, the DDM 1 installed at the door
8. Since the power supply of the PDM 20 and the load is supplied from a power supply circuit having a protection function of the BCM 14, it is not necessary to use a coaxial structure line as the power supply line, and an ordinary electric wire can be used. Therefore, the diameter of the wire can be reduced. Further, the semiconductor switching element used in the output circuit may not have a protection function.

FIGS. 8, 9, 10, and 11 show the configuration of an H-bridge circuit that drives the motor in both forward and reverse directions. First, FIG. 8 will be described. The logic circuit 1050 includes four semiconductor switching elements 101 having no short-circuit protection function based on two control signals from the control circuit.
0, 1020, 1030, and 1040 are converted into H-bridge control signals. That is, at the time of forward rotation, the semiconductor switching element 1020 and the semiconductor switching element 1030 are turned on to supply a current to the motor 1060, and at the time of reverse rotation, the semiconductor switching element 1010 and the semiconductor switching element 1040 are turned on to supply a reverse current to the motor. Convert to a flowing signal. FIG. 9 shows a semiconductor switching element 1010 having a short-circuit protection function for two upstream semiconductor switching elements constituting an H-bridge.
FIG. 10 shows a semiconductor switching element 103 having a short-circuit protection function by connecting two downstream semiconductor switching elements constituting an H-bridge.
FIG. 11 shows a semiconductor switching element 1010a, 1020a, 1030a, 1010a, 1030a, 1030a, 1030a, 1030a, 1030a, which has a short-circuit protection function for all four upstream and downstream semiconductor switching elements constituting an H-bridge.
40a. FIG. 8 does not have the short-circuit protection function in the semiconductor switching element forming the H-bridge, so that a short-circuit protection function is required in another place. FIG. 9 uses a semiconductor switching element having a short-circuit protection function upstream, so that it is protected even if the load is short-circuited, and is protected even if the power supply connected to the load is short-circuited to the ground. However, when the power supply connected to the load is short-circuited to the power supply side, the downstream semiconductor switching element is destroyed. FIG. 10 uses a semiconductor switching element having a short-circuit protection function downstream, so that it is protected even if the load is short-circuited, and is protected even if the wire connected to the load is short-circuited to the power supply side. You. However, when the electric wire connected to the load is short-circuited to the ground, the semiconductor switching element on the downstream side is broken. On the other hand, FIG. 11 uses a semiconductor switching element having a short-circuit protection function at both the upstream and downstream sides. Is protected even if short-circuited to the power supply side.

The proper use of the four H-bridge circuits will be described. A module which is supplied with power from the power bus 12, specifically, the FIM in the embodiment of FIG.
5, there are only two fusible links 4e and 4f upstream of the BCM 14 and the RIM 29. If the output circuit does not have a short-circuit protection function when the load short-circuits,
Since the entire loop power system becomes inoperable, the FIM5
(FIG. 3), the motor driven H-bridge circuit in the BCM 14 (FIG. 4), and the RIM 29 (FIG. 5) include FIGS.
You need to use one of them. However, PCM10 (FIG. 6), ABS11, A / C16, etc. in the embodiment of FIG.
Since a fuse is provided for each function and for each load like the load of the PCM 10 in FIG. 6, even if the H-bridge circuit does not have a short-circuit protection function, a fatal failure will not occur. In the embodiment, the H-bridge circuit having no short-circuit protection function shown in FIG. 8 is used. Of course, there is no problem even if the H-bridge circuits shown in FIGS. 9, 10 and 11 are used. Similarly, for the power supply of the DDM 18 and the PDM 20, the H-bridge circuit having no short-circuit protection function shown in FIG. I'm using

Next, an overcurrent detection circuit in the output circuit of the module shown in FIGS. 3, 4, 5, 6, and 7 will be described. FIG. 12 shows the configuration of the overcurrent detection circuit. 20
Reference numeral 20 denotes a shunt resistor. One end on the upstream side is connected to a power supply line, and one end on the downstream side is connected to a plurality of semiconductor switching elements for driving a load. It is configured to flow through the resistor 2020. The potential difference between both ends of the shunt resistor 2020 is amplified by the amplifier circuit 2010, and the current flowing through the shunt resistor by the A / D converter 2000 of the control circuit is
That is, the sum of the currents flowing through the connected loads is detected. In the present embodiment, by detecting this current, a dead short failure of the load, a leak short failure of the load, a combined failure of the load dead short failure and the dead short failure of the semiconductor switching element of the output circuit, and the like are detected, and the fail safe operation is performed. Is working.

The method of detecting the failure and the method of fail-safe in the modules of FIGS. 3, 4, 5, 6, and 7 will be described with reference to the processing flowcharts of FIGS. FIG. 13 shows a method of detecting a load short-circuit fault and a fail-safe method. First, in step 6000, the current IT flowing to the overcurrent detection circuit is measured by the A / D converter 2000 in FIG. Next, in step 6010, it is determined whether the measured current IT is equal to or larger than a predetermined allowable value. The predetermined allowable value is a value that is equal to or less than a value at which any part of the module will be destroyed if the value exceeds this value, and is a value set to be equal to or greater than the current value when all the loads connected to the module are operating. If it is determined in step 6010 that the current IT is equal to or less than the allowable value, it is determined that there is no fatal dead short failure, and step 6200 in FIG. 14 is executed. In step 6010, the current IT
Is larger than the allowable value, it is determined that one of the loads is short-circuited, and the steps from step 6020 are executed. In step 6020, all the semiconductor switching elements of the output circuit are turned off to turn off all the loads that are currently turned on. In step 6030, the number m of the loads that have been turned on is calculated, and in step 6040, the current IT is measured again. Here, since all the semiconductor switching elements are turned off, the current should not flow unless the semiconductor switching elements have failed. To determine this, the current I measured again in step 6050
It is compared whether T (current when all the semiconductor switching elements are turned off) exceeds the allowable value. Here, if the current IT is equal to or larger than the allowable value, it means that the semiconductor switching element has failed and the load has also suffered a dead short failure. The reason is that if the load is normal, the current I
T should not be greater than the allowed value. Therefore, in order to cut off the loop power supply system so that power is not supplied to the failure point, first in step 6150,
Turn off the load power cutoff circuit of the faulty module,
In order to turn off the load power cutoff circuit of the module connected to the failed power supply system, in step 6160, failure information is transmitted to other modules by multiplex communication. The module that has received this information immediately turns off the load power cutoff circuit if the information indicates that the module turns off its own load power cutoff circuit. By doing so, the failed power supply system can be shut off,
It is possible to prevent the current from continuing to flow. Further, in step 6170, the location of the failure and the content of the failure are displayed or stored as service information at the dealer. The stored information is stored in the diagnostic device 1 of FIG.
3 can be read out. A method of shutting down a failed power supply system will be described in more detail with reference to the embodiment of FIG. As an example, it is assumed that both the fuel pump 392 connected to the RIM 29 in FIG. 5 and the semiconductor switching element 364 for driving the same have a dead short failure. At that time, the overcurrent detection circuit 361 of the RIM 29
When a failure is detected based on the current flowing through the power supply, first, the relay contact of the load power supply cutoff circuit 310 of the failed power supply system is turned off, and the power supply line 12E of the failed power supply system and the power supply line 12D of the normal power supply system are disconnected. Further, since the power supply line 12E of the failed power supply system is connected to the power supply line 12F, the relay contact of the second load power supply cutoff circuit 210b of the BCM 14 of FIG. 6 to which the power supply line 12F is connected is turned off. The power supply line 12F of the failed power supply system and the power supply line 12G of the normal power supply system are cut off. In this way, only the failed power supply system is shut off, so that the load connected to the normal power supply system operates normally.

If the current IT measured again in step 6050 is equal to or less than the allowable value, the semiconductor switching element has not failed, but one of the loads is dead short-circuited. After step 6060, it is determined which load is short-circuited. Step 60
At 60, a numerical value n for how many times the following processing is repeated is initialized to 1. In step 6070, after turning on only one of the loads turned off in step 6020, step 607
At 0, the current IT is measured, and at step 6090 the current IT is compared to the same predetermined tolerance as above. At this time, if the current IT is equal to or more than the allowable value, step 6070
In step 6110, the load turned off is dead-short unless the return condition is satisfied. Also at this time, the failure information is displayed and stored in step 6120 in the same manner as described above. If the current value IT is equal to or less than the allowable value in step 6090, it is determined that the load is not dead-short.
In step 6100, the semiconductor switching element for driving the load is turned on, and the normal operation is performed. This is 1
Although the diagnosis of the loads is completed, in order to diagnose the remaining loads, the numerical value n is increased by 1 in step 6130, and it is compared in step 6140 whether or not all of the loads have been completed. The processing of step 6070 and subsequent steps is repeated, and when the processing is completed, the next processing is step 620 in FIG.
Execute 0.

FIG. 14 shows a process of a method of detecting a current not less than a normal value due to a load leak or the like, instead of a dead short, and turning off the load. In step 6210, the current value IT is measured. Step 62
In step 20, the normal maximum current value ILmax and minimum ILmin of all the operating loads when the current IT is measured are searched, and the number m of operating loads is calculated. For example, FIG. 15 shows an example of the center value of the normal current of the lamp after the operation starts, and FIG. 16 shows an example of the center value of the normal current of the motor after the operation starts. Is shown. Normal current data of all such loads is stored in the memory in advance, and the data is searched for, and the variation data is added to the searched center value,
In Equations 1 and 2, the maximum current value IL of all loads at normal time
Calculate max and minimum ILmin.

ILmax = Normal current x (1 + variation): Expression 1 ILmin = Normal current x (1−variation): Expression 2 In step 6230, the maximum value of the normal current value of the load that is currently turned on. , The minimum sum ITmax, ITmin is given by Equation 3,
It is calculated by Equation 4.

ITmax = ΣILmax_n (n = 1 to m): Equation 3 ITmin = ΣILmin_n (n = 1 to m): Equation 4 For example, if the two loads shown in FIGS. 15 and 16 are operating, the sum is , And the current value as shown in FIG. Next, at step 6240, the abnormality determination maximum current value INGma
x is calculated by Expression 5, and the abnormality determination minimum current value INGmin is calculated by Expression 6.

INGmax = ITmax + A: Equation 5 INGmin = ITmin−A: Equation 6 A in Equations 5 and 6 is a predetermined constant value of 0 or more. In this embodiment, the abnormality determination current value is calculated by adding a constant value, but may be calculated by calculating a ratio. In step 6250, the current value IT measured in step 6210 and the abnormality determination current value calculated in step 6240 are compared. If the current value IT is larger than the abnormality determination minimum current value INGmin and smaller than the abnormality determination maximum current value INGmax, the process is terminated because it is normal. At other times, it is determined that any of the loads has an abnormality, and the following processing is executed to identify the abnormal load. In step 6260, a numerical value n representing how many times the following processing is repeated is initialized to 1. Step 627
1 ms when only one of the loads currently on is turned off at 0
Thereafter, in step 6270, the current ITnew at that time is measured, and in step 6290, the current value (IT-ITnew) changed by the turning off is larger than the maximum current value ILmax of the off load determined by searching in step 6220. If it is smaller and larger than the maximum current value ILmin, the load is normal. Therefore, in step 6300, the semiconductor switching element that drives the load is turned on, and the operation at the time of normal operation is performed. If it is determined in step 6290 that the load is abnormal, in step 6310, the load is turned off unless a return condition is satisfied. In step 6320, the failure information is displayed or stored. In order to diagnose the remaining load, the numerical value n is incremented by 1 in step 6330, and it is compared in step 6340 whether or not all the processes have been completed. If not completed, the processes in and after step 6270 are repeated. As described above, when both the load and the semiconductor switching element are short-circuited, the power supply system is cut off, so that the loop power supply system is not affected. Further, if a short circuit and a rare short circuit of the load are detected, only the corresponding semiconductor switching element can be cut off, so that only a faulty portion can be isolated and other loads are not affected. Further, in this embodiment, the semiconductor switching element having a built-in function of detecting and shutting off the over-temperature is used. However, since the current of each load can be detected as described above, the protection function of the semiconductor switching element is based on the semiconductor switching element. Only for the purpose of not destroying the element,
If there is an overcurrent limiting function that may have a large variation, short-circuit protection can be sufficiently performed, and the configuration of the semiconductor switching element can be simplified.

FIGS. 18, 19, and 20 are block diagrams of another module FIM5, BCM14, RIM29 of the embodiment of FIG. 2, and the other modules PCM10, DDM18, PDM
20 is the same as the embodiment shown in FIGS. 6 and 7. FIG.
Is a configuration diagram of the FIM5, and only different points of the configuration diagram of the FIM5 in FIG. 3 will be described. In FIG. 3, the overcurrent detection circuit 16
18, the FIM 5 of FIG. 18 does not have an overcurrent detection circuit, and has a temperature detection circuit 169 for detecting the temperature of the heat sink and a temperature sensor 1 for detecting the peripheral temperature.
83. Similarly, the BCM shown in FIGS.
14 and RIM 29 also have no overcurrent detection circuit, and have temperature detection circuits 209 and 369 for detecting the temperature of the heat sink and temperature sensors 284 and 383 for detecting the peripheral temperature, respectively.

FIGS. 21, 22, and 23 show examples of the configuration of the temperature detection circuit. FIG. 21 includes diodes 3020 to 3050, a resistor 3010 for limiting a current flowing through the diode, and an A / D converter 3000 for inputting a voltage between the resistor 3010 and the diode 3020 and performing A / D conversion. The A / D converter 3000 includes FIM5, BCM14,
CPU 170, 270, 370 of RIM 29
It is built in. 4 of diodes 3020 to 3040
The diodes have characteristics as shown in FIG.
When a current flows in the diode in the forward direction, a forward voltage is generated, and the voltage has a characteristic that changes substantially linearly with temperature. When the temperature is low, the forward voltage is high, and when the temperature is high, the forward voltage is low. Temperature can be detected by connecting diodes having such characteristics in series and measuring the voltage at that time. FIG.
In this example, four diodes are connected in series, in order to make the voltage at about 25 ° C., which is room temperature, approximately half the A / D reference voltage (5 V). By doing so, the detection accuracy is improved and the detection range is widened. However, it is natural that the temperature can be detected by only one without connecting four. As also shown in the characteristic diagram of FIG. 24, the forward voltage of the diode changes depending on the forward current. Therefore, in the case of the configuration shown in FIG. 21, when the forward voltage of the diode changes according to the temperature, the forward current flowing through the diode also changes, so that the temperature characteristics are not linear and the accuracy decreases. In FIG. 22, a constant current source 3060 that keeps the current flowing through the diode constant is provided instead of the resistor 3010 that limits the current flowing through the diode in FIG. 21 so that the accuracy does not decrease. By doing so, the current flowing through the diode does not change even when the temperature changes, so that the temperature can be detected with higher accuracy. FIG. 23 is a configuration example of another temperature detection circuit.
FIG. 23 shows a temperature detecting resistor 3 having characteristics as shown in FIG.
080, a resistor 3070 connected to the temperature detecting resistor 3080, and the resistor 3070 and the temperature detecting resistor 308.
A / D converter 300 for inputting a voltage between 0 and performing A / D conversion
0. The characteristics of the temperature detecting resistor 3080 are classified into two types, as shown in (a) of FIG. 25, the resistance value decreases as the temperature increases, and as shown in (b), the resistance value increases as the temperature increases. When accuracy is required on the high temperature side, a temperature detecting resistor having the characteristic (b) is used, and when accuracy is required on the low temperature side, a temperature detecting resistor having the characteristic (a) is used.

FIG. 26 shows a typical example of the module structure. Reference numeral 4010 denotes a plastic case integrated with a connector for connection to the outside. The bottom of the plastic case 4010 is closed by an aluminum base 4080, and an aluminum foil on which a copper foil pattern for forming a circuit is pasted. Printed circuit board 4070 is mounted. The aluminum printed board 4070 mainly includes the semiconductor elements 4130 to 4320 that generate a large amount of heat and the temperature detecting element 4030.
00 is mounted. These semiconductor elements 4130 to 432
0 denotes the semiconductor elements 163 to 168 in the output circuit 160 in the FIM 5 in FIG. 18, and the power supply circuit 200 and the semiconductor element 20 in the output circuit 260 in the BCM 14 in FIG.
3 to 204 and 263 to 266, and RIM2 in FIG.
Reference numeral 9 denotes semiconductor elements 363 to 368 in the output circuit 360. The temperature detecting element 4000 is the diode 3030 to 3050 in FIGS. 21 and 22, and the temperature detecting resistor 3080 in FIG. This temperature detecting element is mounted substantially at the center of a printed board 4070 made of aluminum. The ceiling of the plastic case 4010 is covered with a plastic cover 4020 to prevent water from entering.

Reference numeral 4030 denotes a printed circuit board 407 made of aluminum.
This is a printed circuit board on which the circuit elements (for example, CPU, etc.) of FIGS. 18, 19, and 20 which are not mounted on a printed circuit board 0 are connected. Further, by connecting the printed board 4070 made of aluminum and the terminal 4050 with the wire bonding wire 4040, the connection with the outside is made. As described above, since the semiconductor element as the heating element is mounted on the aluminum printed board 4070 and further bonded to the aluminum base 4080 for radiating the temperature to the outside air, the heat dissipation is good, and the heat generation of the element is reduced. Can be suppressed.
Further, since the temperature detecting element 4000 is mounted at the center of the aluminum printed board 4070, it is possible to detect almost the average of the heat generated by the semiconductor elements mounted on the aluminum printed board 4070. Further, by mounting the heating element on an aluminum printed board 4070 and mounting other components on another printed board, miniaturization becomes possible.

FIG. 27 shows another representative example of the module structure. The difference from FIG. 26 is that the temperature detecting elements are mounted at two positions on a printed circuit board 4070 made of aluminum. By doing so, the temperature can be detected more accurately.

FIG. 28 is a processing flow of failure detection and fail-safe when one temperature detecting element is provided. In step 7010, since it is normal at first, step 703
0, and the temperature Tf at the position of the temperature detection element 4000 in FIG. 26 is measured by the temperature detection circuit in FIG. 21, FIG. 22, or FIG. In step 7040, the measured temperature T
It is determined whether or not f is 150 ° C., and if f is 150 ° C. or more, in step 7050 all the semiconductor switching elements of the output circuit are turned off in order to turn off all loads that are currently on. Further, in step 7060, the load power cutoff circuit of the failed module is turned off, and the load power cutoff circuit of the module connected to the faulty power supply system is turned off. Transmit to the module by multiplex communication. The module that has received this information immediately turns off the load power cutoff circuit if the information indicates that the module turns off its own load power cutoff circuit. By doing so, the failed power supply system can be cut off, and the current can be prevented from continuing to flow. Further, in step 7080, the location of the failure and the content of the failure are displayed and stored as service information at the dealer. The stored information can be read by the diagnostic device 13 shown in FIG. Step 70
If it is determined at 40 that the temperature Tf is 150 ° C. or lower, normal control is performed. If this routine is executed after it is determined that an abnormality has occurred, it is determined that an abnormal process is being performed in step 7010, and if the condition for canceling the abnormal process is not satisfied in step 7020, the process ends and the cancel condition is satisfied. If so, step 7030 and subsequent steps are executed again. In the present embodiment, the release condition is when the ignition switch is turned off, but this naturally changes depending on the control contents. By doing so, once an abnormality is detected, the current is interrupted until the release condition is satisfied. A simple description of when an abnormality is detected will be described. First, in the first case, when a load (for example, the horn 8 of the FIM 5 in FIG. 18) dead-shortens, the horn 8 is sounded, and when the semiconductor switching element 166 is turned on, a very large current flows. It generates heat and becomes hot. This heat is transmitted to the temperature detection element 4000 and exceeds 150 ° C. At this time, if only the semiconductor switching element of the horn is turned off, no current flows and no heat is generated, but if the semiconductor switching element is also short-circuited, the current cannot be cut off. Therefore, the load power cutoff circuit of the module is also turned off. Another case is when the motor is locked. In the description, it is assumed that the washer motor of the FIM 5 in FIG. 18 is locked. This will be described with reference to FIG. When the motor is not locked, since the current is small, the temperature rise is small and the temperature does not exceed the guaranteed temperature of the semiconductor. However, when the motor is locked, a current several times higher than normal flows and the temperature rise is large. In such a case, when the temperature exceeds the guaranteed temperature of the semiconductor, an element which performs a protection function of the semiconductor switching element itself is used as described above in the present embodiment, but a temperature detection for operating this protection function is performed. Because of the large error, some of them are activated by the protection function and turn off the load, while others are not activated by the protection function and continue to be driven without turning off the load. As described above, there is a problem that the function is different if the temperature detection error is large. Therefore, as in the present invention, the current can be reliably cut off by detecting the temperature with a temperature detecting element different from the protection function of the semiconductor switching element and cutting off the current.

FIG. 29 is a processing flow of failure detection and fail-safe when there are two temperature detecting elements. At step 7110, since it is normal at first, step 713
0, and the temperature detection elements 4000, 4005 in FIG.
Are measured by a temperature detection circuit. At step 7140, the measured temperature Tf1 or T
It is determined whether f2 is 150 ° C.
If so, in step 7150 all the semiconductor switching elements of the output circuit are turned off in order to turn off all the loads that are currently on. Further, in step 7160,
Turn off the load power cutoff circuit of the faulty module,
Further, in order to turn off the load power cutoff circuit of the module connected to the failed power supply system, in step 7170, failure information is transmitted to other modules by multiplex communication. The module that has received this information immediately turns off the load power cutoff circuit if the information indicates that the module turns off its own load power cutoff circuit. By doing so, the failed power supply system can be shut off,
It is possible to prevent the current from continuing to flow. Further, in step 7180, the location of the failure and the content of the failure are displayed or stored as service information at the dealer. The stored information is stored in the diagnostic device 1 of FIG.
3 can be read out. In step 7140, both of the temperatures Tf1 and Tf2 are set to 150
If the temperature is determined to be lower than or equal to ° C, normal control is performed. If this routine is executed after it is determined to be abnormal, step 711 is executed.
At 0, it is considered that an abnormal process is being performed. If the condition for canceling the abnormal process is not satisfied at step 7120, this process ends.
And so on. In the present embodiment, the release condition is when the ignition switch is turned off, but this naturally changes depending on the control contents.
The processing according to FIGS. 28 and 29 is the minimum processing necessary to prevent the firing or the like when the load or the load driving element has failed. A method for specifying a failure point when the structure is as shown in FIGS. 26 and 27 will be described below.

FIG. 30 shows a process in which a load in which an overcurrent is flowing is specified, the driving of the load is stopped, and a failure location is stored and displayed. In step 8010, the ambient temperature Ta and the temperature Tf at the position of the temperature detecting element 4000 in FIG.
Is measured by the temperature detection circuit of FIG. 21 or FIG. 22 or FIG. In step 8020, a temperature rise value Tfd = Tf−Ta at the position of the temperature detection element 4000 is calculated based on the ambient temperature Ta and the temperature Tf at the position of the temperature detection element 4000. Next, at step 8030, the temperature detecting element 40
The predicted value of the normal temperature rise at the position 00 is calculated. If the load is normal, a normal current flows through the load and the load driving element, and the current causes the semiconductor switching element, which is the load driving element, to generate heat. The generated heat is radiated by the aluminum substrate and the aluminum base. Temperature detection element 4
The temperature at the position 000 is determined by the amount of heat generated by the load driving element and the thermal resistance between the load driving element and the position of the temperature detecting element 4000. The thermal resistance between the load driving element and the position of the temperature detecting element 4000 is determined by the thermal conductivity and the distance between the load driving element and the position of the temperature detecting element 4000. As a result, the relationship between the current and the temperature rise over time for a lamp is as shown in FIG. 32, and the relationship between the current and the temperature rise over time for a load such as a motor is as shown in FIG. . FIG.
When the loads 2 and 33 are simultaneously driven as shown in FIG. 34, the temperature rise value is a temperature rise value obtained by adding the individual temperature rise values. Therefore, the temperature rise characteristics of all the loads under normal conditions as shown in FIGS. 32 and 33 are stored in the memory as table data, the temperature rise value of the currently driven load is obtained from the table data, and these are added. Thus, it is possible to calculate the predicted value of the temperature rise when the position of the temperature detecting element 4000 is normal in step 8030. In addition, the temperature rise characteristics of all the loads in the normal state are not stored in the memory as table data, and the normal current of the driven load, the load driving element and the temperature detecting element 400 are not stored.
It can also be obtained by calculation from the distance to the zero position and the thermal conductivity. If it is obtained by calculation, even if the current of the load driven by the load driving element mounted on the aluminum substrate is changed or the position of the load driving element is changed, the data is stored in order to store the table data. There is no need to acquire it, and changes can be made easily.

In step 8040, the temperature rise value T
If fd exceeds a value obtained by adding the predetermined value α to the predicted temperature rise value, it is possible that one of the loads currently turned on is abnormal and an overcurrent is flowing, or the load drive element is not turned on. First, whether the load drive element is abnormal and is passing current to the load. Therefore, the abnormal part is specified by the processing after step 8050. First, in step 8050, the number m of the loads that are currently turned on and the probability of abnormality are arranged and ranked in descending order. In the present embodiment, the load that was turned on last before the abnormality was detected is ranked n = 1 with a high abnormality probability, and the load that was turned on earliest is ranked n = m with a low abnormality probability. In step 8060, the number of repetitions n is initialized to 1, the n-th load is turned on in step 8070, and after waiting for a predetermined time in step 8080, the ambient temperature Ta and FIG.
The temperature Tf at the position of the temperature detection element 4000 of FIG.
Alternatively, it is measured by the temperature detection circuit of FIG. 22 or FIG.
In step 8090, the ambient temperature Ta and the temperature detection element 4
The temperature detection element 4000 is determined by the temperature Tf at the position 000.
The temperature rise value Tfd = Tf-Ta at the position is calculated. Next, in step 8100, a predicted value of the temperature rise at the position of the temperature detecting element 4000 is calculated. In step 8110, if the temperature rise value Tfd is equal to or less than the value obtained by adding the predetermined value α to the predicted temperature rise value, it is determined that the currently turned off load is abnormal, and step 8160 is executed to display the failure information. Or store the information as service information at the dealer to identify the failure location and end the process.
On the other hand, if the temperature increase value Tfd exceeds the value obtained by adding the predetermined value α to the predicted temperature increase value in step 8110, whether the currently turned off load is normal and another load is abnormal and an overcurrent is flowing. That is, whether the load driving element is abnormal and the current is flowing to the load even though the load driving element is not turned on. Therefore, in step 8120, step 8
In step 813, the load that was turned off in step 070 is turned on again.
In order to diagnose the next load at 0, n is incremented by 1, and it is determined at step 8140 whether or not n> m has been checked for all the loads that are currently on. If it is determined in step 8140 that all the checks have not been completed, step 8070 and subsequent steps are repeated to diagnose all the ON loads. If it is determined in the diagnosis of all the loads that are on that all the loads are normal, it is determined in step 8120 that the load drive element that is currently off has failed and an abnormal current is flowing, and the information is displayed. After that, the process is terminated. At this time,
Although it is possible to turn on the off-loads one by one to identify the fault location, it is possible for the driver to feel uncomfortable if the off-load is turned on regardless of the driver's intention under normal control. In the present embodiment, such processing is not performed, and only an abnormal display is performed. In order to specify the abnormal part, the processing can be performed by performing the processing of FIG. 36 performed by the dealer. In step 8040, if the temperature rise value Tfd is equal to or less than the value obtained by adding the predetermined value α to the predicted temperature rise value, it is determined that an overcurrent is not flowing, and the processing in FIG. 31 is executed. In this way, the location where the overcurrent is flowing can be specified and cut off, so that the continuous overcurrent can be prevented.

The process shown in FIG. 31 is a process for detecting an open failure of a load or a load driving element. Step 82
In 40, if the temperature rise value Tfd obtained in step 8020 of FIG. 30 exceeds the value obtained by subtracting the predetermined value β from the predicted temperature rise value obtained in step 8030, the actual temperature rise value is within the allowable range of the predicted value. Since it is within the range, it is determined that there is no abnormality, and the process ends. At step 8240,
If the temperature rise value Tfd is equal to or smaller than the value obtained by subtracting the predetermined value β from the predicted temperature rise value, the processing for specifying the fault load in step 8250 and thereafter is executed. In step 8250, the order is sorted and ranked in order from the number m of the loads currently turned on and the probability of abnormality. In the present embodiment, the load that was turned on last before the abnormality was detected is set to the rank n = 1 with the highest abnormality probability, and the load that was turned on earliest is set to the rank n = m with the low abnormality probability.
And In step 8260, the number of repetitions n is set to 1
26, the n-th load is turned on in step 8270, and after waiting for a predetermined time in step 8280, the ambient temperature Ta and the temperature T at the position of the temperature detecting element 4000 in FIG.
f is measured by the temperature detection circuit of FIG. 21 or FIG. 22 or FIG. In step 8290, a temperature rise value Tfd = Tf−Ta at the position of the temperature detection element 4000 is calculated from the ambient temperature Ta and the temperature Tf at the position of the temperature detection element 4000. Next, at step 8300, the temperature detecting element 4
The predicted value of the temperature rise at the position of 000 is calculated. In step 8310, if the absolute value of the difference between the temperature rise value Tfd and the predicted temperature rise value is less than the predetermined value γ, it is determined that the currently turned off load is abnormal, and step 8350 is executed. By displaying the information or storing it as service information at the dealer, the failure location is specified and the processing is terminated. On the other hand, in step 8310, if the absolute value of the difference between the temperature rise value Tfd and the predicted temperature rise value is equal to or greater than the predetermined value γ, the currently turned off load is normal and the other load is abnormal and no current is flowing. Or, the current is not flowing from the load driving element to the load even though the load driving element is turned on. Therefore, in step 8320, the load that was turned off in step 8270 is turned on again,
At 8330, in order to diagnose the next load, n is increased by 1, and it is determined at step 8340 whether or not n> m has been checked for all loads that are currently on. If it is determined in step 8340 that all the checks have not been completed, step 8270 and subsequent steps are repeated to diagnose all the ON loads. If it is determined that all the loads are normal in the diagnosis of all the loads that are turned on, this processing is ended. By doing so, it is possible to specify a load that has failed in the open state.

FIG. 36 shows a processing flow for specifying a fault location by diagnosis at the dealer. First, step 90
At 10 all loads are turned off. Next, step 902
Initialize the load order n to be diagnosed with 0 to 1 and step 9
030 and subsequent steps are executed. In step 9030, the corresponding load driving element is turned on to supply current to the n-th load. Then, depending on the driven load, FIG.
33, a current flows as shown in FIG. Therefore, after waiting for a predetermined time during which an abnormality can be detected due to a temperature rise in step 9040, the ambient temperature Ta and the temperature Tf at the position of the temperature detecting element 4000 in FIG. 26 are measured by the temperature detecting circuit in FIG. 21, FIG. 22, or FIG. . In step 9050, the ambient temperature Ta and the temperature Tf at the position of the temperature detecting element 4000
Temperature rise value Tfd = Tf at the position of temperature detection element 4000
Calculate Ta. Next, in step 9060, a predicted value of the temperature rise at the position of the temperature detecting element 4000 is calculated.
In step 9070, if the temperature rise value Tfd exceeds the value obtained by adding the predetermined value α to the predicted temperature rise value, it is determined that the currently turned on load is abnormal in the short-circuit state or the rare short-circuit state, and step 9080 is executed. And displays the failure information. On the other hand, in step 9070,
If the temperature rise value Tfd is equal to or less than the value obtained by adding the predetermined value α to the predicted temperature rise value, the temperature rise value T
If fd is equal to or less than the value obtained by subtracting the predetermined value β from the predicted temperature rise value, it is determined that the load that is currently turned on is abnormal in the open state, and step 9090 is executed to display the failure information. If the temperature rise value Tfd exceeds the value obtained by subtracting the predetermined value β from the predicted temperature rise value in step 9070, the load is regarded as normal, so that step 9110 is performed.
Indicates normal. Step 9080, Step 90
After the failure display at 90 and the normal display at step 9110, step 9120 is performed to diagnose the next load.
Then, the load that was turned off in step 9030 is turned on again,
In step 9120, n is incremented by 1 to diagnose the next load, and it is determined in step 9130 whether or not n has checked all the loads, in order to determine whether n> m. If it is determined in step 9130 that all the checks have not been completed, step 9030 and subsequent steps are repeated to diagnose all loads. In this way, it is possible to detect a short circuit or an open state abnormality of all loads.

[0068]

According to the present invention, the number of fuses is small, and the wire harness for supplying power can be shortened, thin, or reduced in number. According to another aspect of the present invention, not only the occurrence of a short circuit abnormality in the power supply line can be prevented, but also the abnormal point at the time of the occurrence of the short circuit abnormality can be specified. Further, the short-circuit section can be separated. In another invention, an overcurrent detection circuit is provided, so that if there is a faulty load, it can be disconnected. In still another invention, the current consumption of the power supply device when the vehicle is not operating can be reduced.

[Brief description of the drawings]

FIG. 1 is a system layout diagram of an automobile to which the present invention is applied.

FIG. 2 is an embodiment of an overall system of an automobile to which the present invention is applied.

FIG. 3 is a configuration diagram of an FIM module of the system of FIG. 2;

FIG. 4 is a BCM module configuration diagram of the system of FIG. 2;

FIG. 5 is a configuration diagram of an RIM module of the system of FIG. 2;

FIG. 6 is a configuration diagram of a PCM module of the system of FIG. 2;

FIG. 7 is a configuration diagram of a DDM module of the system of FIG. 2;

FIG. 8 is a motor drive H-bridge circuit configuration 1;

FIG. 9 is a motor drive H-bridge circuit configuration 2.

FIG. 10 shows a motor drive H-bridge circuit configuration 3;

FIG. 11 is a motor drive H-bridge circuit configuration 4;

FIG. 12 shows an overcurrent detection circuit configuration using a shunt resistor.

FIG. 13 is a diagram illustrating an algorithm for detecting and protecting a short circuit between a load and an output circuit.

FIG. 14 is an algorithm of a load overcurrent detection and protection operation.

FIG. 15 shows lamp current characteristics.

FIG. 16 shows motor current characteristics.

FIG. 17 shows current characteristics during multiple driving.

FIG. 18 is another FIM module configuration diagram of the system of FIG. 2;

FIG. 19 is another BCM module configuration diagram of the system of FIG. 2;

FIG. 20 is another RIM module configuration diagram of the system of FIG. 2;

FIG. 21 is a configuration example 1 of a temperature detection circuit.

FIG. 22 shows a temperature detection circuit configuration 2.

FIG. 23 shows a third temperature detection circuit configuration.

FIG. 24 shows characteristics of diodes of the temperature detection circuits of FIGS. 21 and 22.

FIG. 25 shows characteristics of a temperature detecting element of the temperature detecting circuit of FIG. 23;

FIG. 26 is a structural diagram 1 of a module.

FIG. 27 is a structural diagram 2 of a module.

FIG. 28 is an algorithm for detecting a short-circuit between a load and an output circuit due to temperature and protecting operation in the module structure of FIG. 26;

FIG. 29 is an algorithm for detecting a short-circuit between a load and an output circuit due to temperature and protecting operation in the module structure of FIG. 27;

FIG. 30 is an algorithm 1 of load overcurrent detection and protection operation based on temperature.

FIG. 31 shows an algorithm 2 for detecting and protecting a load overcurrent based on temperature.

FIG. 32 shows a temperature rise characteristic due to a lamp current.

FIG. 33 shows a temperature rise characteristic due to a motor current.

FIG. 34 is a graph showing a temperature rise characteristic caused by a current during multiple driving.

FIG. 35 shows a relationship between a temperature rise characteristic due to a motor lock current and a shutdown temperature.

FIG. 36 is an algorithm for detecting a load abnormality based on temperature in the diagnostic mode.

[Explanation of symbols]

3: Battery, 5: FIM, 10: PCM, 11: AB
S, 12A to 12H: power line, 13: diagnostic device, 14: B
CM, 14 radio, 16 A / C, 17A-17D ...
Connector, 18 ... DDM, 20 ... PDM, 25 ... SD
M, 29: RIM, 30: Multiple communication lines, 100: FIM
Power supply circuit 110, FIM load power cutoff circuit,
120: FIM control system power supply circuit, 130: FIM short detection circuit, 140: FIM communication circuit, 150 ...
Input circuit of FIM, 160 output circuit of FIM, 169
... FIM temperature detection circuit, 170 ... FIM control circuit,
180: FIM input signal, 183: FIM temperature sensor, 190: FIM load, 4000: temperature detection element.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hiroyuki Saito 2520 Oji Takaba, Hitachinaka City, Ibaraki Prefecture Inside the Automotive Equipment Division of Hitachi, Ltd. (72) Inventor Shuyuki Okamoto 4-6 Kanda Surugadai, Chiyoda-ku, Tokyo Inside Hitachi, Ltd. (72) Inventor Yuichi Kuramochi 2520, Ojitakaba, Hitachinaka City, Ibaraki Prefecture Hitachi, Ltd. In the Automotive Equipment Division (72) Inventor Ichiro Osaka 4-6 Kanda Surugadai, Chiyoda-ku, Tokyo F-term in Hitachi, Ltd. 5G053 AA01 BA01 BA06 CA01 DA01 DA03 EA01 EA05 EA09 EB01 EC03 FA05 5G065 BA04 EA02 FA01 GA09 LA02 LA07 PA01

Claims (11)

[Claims] 1. A power supply installed in a vehicle, a power line wired from the power supply to the vehicle, a power semiconductor element connected in series between the power line and an electric load, and an abnormality in the load or the power semiconductor element. Abnormality detecting means for detecting a load or a power semiconductor element when an abnormality occurs in the electric power supply path between the power supply and the electric load based on an electric signal output from the abnormality detecting means when the abnormality or the electric circuit breaker. A vehicle power supply device having control means for shutting off a power semiconductor element. 2. A power semiconductor element for controlling a state of supplying power to a load mounted on a vehicle, a heat conductor for radiating heat generated by the power semiconductor element, a temperature detecting means for detecting a temperature of the heat conductor, A load control device for a vehicle for controlling an operation state of the power semiconductor element in relation to a temperature detected by the temperature detecting means. 3. A load control device for a vehicle having a power semiconductor element, a power cutoff circuit for shutting off power supplied to the power semiconductor element, a heat conductor radiating heat generated by the power semiconductor element, Temperature detecting means for detecting a temperature, and a load control device for a vehicle for shutting off the power semiconductor element and / or a power cutoff circuit when a temperature detected by the temperature detecting means reaches a specific temperature. 4. The temperature according to claim 1, wherein the temperature at which the power semiconductor element or the power supply cutoff circuit is cut off is:
A load control device for a vehicle that sets the guaranteed temperature of the power semiconductor element. 5. The vehicle load control device according to claim 1, wherein the temperature at which the semiconductor element or the power cutoff circuit is shut off is determined by a current flowing through the power semiconductor element. 6. The temperature according to claim 1, wherein the temperature at which the power semiconductor element or the power supply cutoff circuit is cut off is:
A vehicle load control device is determined by a current flowing through the power semiconductor element and an installation distance between the power semiconductor element and the temperature detecting means. 7. The temperature according to claim 1, wherein the temperature at which the power semiconductor element or the power supply cutoff circuit is cut off is:
A load control device for a vehicle, which is determined based on a current flowing through the power semiconductor element, an installation distance between the power semiconductor element and the temperature detecting means, and an ambient temperature. 8. The method according to claim 1, wherein when the power semiconductor element or the power supply cutoff circuit is cut off,
A vehicle load control device for displaying an abnormal state. 9. A vehicle load control device having a power semiconductor element, a heat conductor for radiating heat generated by the power semiconductor element, a temperature detecting means for detecting a temperature of the heat conductor, and a temperature detecting means for detecting a temperature of the heat conductor after the load is turned on. Abnormality detecting means for detecting an abnormal load according to the degree of temperature rise of the power semiconductor element, and a load control device for a vehicle for shutting off a power semiconductor element attached to the load detected as abnormal. 10. A vehicle load control device having a power semiconductor element and a heat conductor for radiating heat generated by the power semiconductor element, a temperature detecting means for detecting a temperature of the heat conductor.
Abnormality detecting means for detecting an abnormal load according to the degree of temperature rise of the power semiconductor element after the load is turned on, means for diagnosing the device in cooperation with the abnormality detecting means by an external operation, and detecting an abnormality. A load control device for a vehicle having a display means for displaying when the vehicle is turned on. 11. The vehicle according to claim 1, wherein the temperature at which the power semiconductor element or the power supply cutoff circuit is cut off is determined by a sum of table data for each load stored in advance. Load control device.