JP6737237B2 - Electronic control circuit - Google Patents

Description

The present invention relates to an electronic control circuit that controls power supply.

When the vehicle is equipped with an electronic control circuit having a control circuit and a monitoring circuit, the control circuit is a microcomputer, etc., and the monitoring circuit monitors the opening and closing of the door of the vehicle and lighting of the interior light to control the monitoring signal. A circuit that outputs to a circuit can be considered.

In such an electronic control circuit, conventionally, when the control circuit is in the operation mode, power is always supplied from the power supply to the monitoring circuit. Therefore, the power consumption in the operation mode of the electronic control circuit is the power consumption Wa (=W1a+W2a) that is the sum of the power consumption W1a of the control circuit and the power consumption W2a of the monitoring circuit.

Further, when the control circuit is in the normal low power mode (deep sleep mode: mode in which the microcomputer or the like is completely stopped), the power consumption in the normal low power mode of the electronic control circuit is the power consumption W1b (<W1a) of the control circuit. The power consumption Ws (=W1b+W2b) is the sum of the power consumption W2b (≈0 [W]) of the monitoring circuit.

However, in the electronic control circuit, since the power is continuously supplied from the power supply to the monitoring circuit in the operation mode of the control circuit, when the power supply is a power storage device such as an auxiliary battery, the charging capacity of the auxiliary battery is Decrease faster.

Therefore, there is known a method of reducing the power supplied from the power supply to the monitoring circuit when the control circuit is in the operation mode to reduce the power consumption of the electronic control circuit. In this method, the power is not continuously supplied from the power supply to the monitoring circuit in the operation mode as in the conventional method, but the power is supplied from the power supply to the monitoring circuit at the time when the monitoring circuit monitors. For example, power is intermittently supplied for a predetermined monitoring time every predetermined time. In the method of supplying power intermittently, a power supply control circuit is added between the power supply and the control circuit, the power supply control circuit is controlled by the control circuit, and power is intermittently supplied from the power supply to the monitoring circuit via the power supply control circuit. Supply.

By performing the intermittent control using the power supply control circuit in this manner, the power consumption of the electronic control circuit is W1c (≈W1a) of the control circuit and the power consumption W2c of the drive time during the intermittent control of the monitoring circuit and the power supply. The power consumption Waa (=W1c+W2c+W3c)<Wa, which is the sum of the power consumption W3c of the drive time during the intermittent control of the control circuit, is satisfied. The power consumption W2c+W3c is smaller than the power consumption W2a because the monitoring circuit and the power supply control circuit perform intermittent control (W2c+W3c<W2a).

As described above, in the electronic control circuit that adds the power supply control circuit to perform the intermittent control, it is possible to reduce power consumption in the operation mode of the control circuit as compared with the conventional electronic control circuit without the power supply control circuit.

Related technologies include Patent Document 1 and Patent Document 2.

Japanese Patent Laid-Open No. 10-225003 JP, 2016-002784, A

However, in the electronic control circuit to which the power supply control circuit is added, even if the control circuit shifts to the normal low power mode, if the circuit configuration requires driving the power supply control circuit to continue supplying power to the monitoring circuit, The circuit must output a control signal (high signal) for driving the power supply control circuit in a normal low power mode to drive the power supply control circuit. Therefore, the power consumption of the electronic control circuit to which the power supply control circuit is added in the normal low power mode is the power consumption of the control circuit (power consumption at the time of outputting a high signal) W1d (>W1b) and the power consumption of the monitoring circuit W2d (≈0[ W]) and the power consumption of the power supply control circuit (power consumption during driving) W3d, the total power consumption Wss (=W1d+W2d+W3d)>Ws. Therefore, in the case where the power source is a power storage device such as an auxiliary battery, in the electronic control circuit to which the power supply control circuit is added, the charge capacity of the auxiliary battery decreases faster when the control circuit is in the normal low power mode.

An object of one aspect of the present invention is to provide an electronic control circuit that can reduce power consumption in an operation mode and a normal low power mode.

An electronic control circuit, which is one mode of the present invention, includes a power supply control circuit connected between a power supply and a control circuit, and the power supply control circuit includes a first switch element for controlling power supply and a first switch element. And a drive circuit for controlling the switch element.

The drive circuit includes a second switch element and a third switch element.
In the normal low power mode, the control circuit stops the second switch element and the third switch element to make the first switch element conductive. In the operation mode, the control circuit intermittently controls the second switch element and the third switch element. Intermittent control is a process of stopping the second switch element and the third switch element to bring the first switch element into conduction, and driving the second switch element and the third switch element to drive the first switch element. The process of shutting off the switch element is alternately and repeatedly executed.

In the power supply control circuit, the control terminal of the control circuit is connected to the input terminal of the drive circuit, the control terminal of the first switch element is connected to the output terminal of the drive circuit, and the first terminal of the first switch element is connected. Is connected to the power supply, and the second terminal of the first switch element is connected to the power supply connection terminal of the monitoring circuit. Further, one of the switches provided inside or outside the monitoring circuit is connected to the ground, and the output terminal of the monitoring circuit and the input terminal of the control circuit are connected. The switch is then in the cutoff state when the control circuit is normally in the low power mode.

An electronic control circuit according to another mode of the present invention includes a control circuit, a power supply control circuit, and a monitoring circuit.
The power supply control circuit is connected between the power supply and the control circuit, and controls the first switch element using the first switch element that controls the power supply, the second switch element, and the third switch element. And a drive circuit that operates.

The monitoring circuit monitors the state of the device by using a switch provided in the device different from the electronic control circuit, and limits the current flowing from the power supply to the switch and the input terminal of the control circuit through the first switch element. One resistance element is provided.

In the operation mode, the control circuit stops the second switch element and the third switch element to bring the first switch element into conduction, and drives the second switch element and the third switch element. Then, the process of interrupting the first switch element is alternately repeated.

In the normal low power mode, the control circuit stops the second switch element and the third switch element to make the first switch element conductive.
When the switch is in the conduction fixation failure state, the control circuit stops the second switch element and the third switch element to bring the first switch element into conduction, and the second switch element and the third switch element. The process of driving the switch element to shut off the first switch element is alternately and repeatedly executed.

Also, the control terminal of the control circuit and the input terminal of the drive circuit are connected, the control terminal of the first switch element and the output terminal of the drive circuit are connected, and the first terminal of the first switch element and the power supply are connected. Connected, the second terminal of the first switching element and the first terminal of the first resistance element are connected, the first terminal of the second resistance element provided in the monitoring circuit and the control circuit The input terminal is connected, the second terminal of the first resistance element, the second terminal of the second resistance element and the first terminal of the switch are connected, and the second terminal of the switch and the ground are connected. Connected.

Power consumption can be reduced in the operating mode and the normal low power mode.

FIG. 3 is a diagram showing an example of an electronic control circuit of the first embodiment. FIG. 9 is a diagram showing an example of an electronic control circuit of the second embodiment. FIG. 8 is a diagram showing an example of an operation of the electronic control circuit of the second exemplary embodiment.

Embodiments will be described below in detail with reference to the drawings.
<Embodiment 1>
FIG. 1 is a diagram showing an embodiment of the electronic control circuit 1. The electronic control circuit 1 includes a control circuit 2, a power supply control circuit 3, and a monitoring circuit 4. The electronic control circuit 1 may be, for example, an EUC (Electronic Control Unit) mounted on a vehicle.

The control circuit 2 controls the power supply control circuit 3 and the monitoring circuit 4, for example, CPU (Central Processing Unit), multi-core CPU, programmable device (FPGA (Field Programmable Gate Array) or PLD (Programmable Logic Device), such as a microcomputer. Etc.) and the like, and has a function of switching between an operation mode and a normal low power mode (deep sleep mode: a mode in which, for example, a microcomputer is completely stopped).

The power supply control circuit 3 includes, for example, a switch element Q1 (first switch element), a switch element Q2 (second switch element), a switch element Q3 (third switch element), a resistance element R1, and a resistance element R2. , A drive circuit 3a including a resistance element R3, a resistance element R4, and a resistance element R5. The switch element Q1 may be a transistor such as a MOSFET (metal-oxide-semiconductor field-effect transistor) or an IGBT (Insulated Gate Bipolar Transistor). The switch elements Q2 and Q3 may be transistors such as bipolar transistors.

The monitoring circuit 4 is supplied with power from the power source BT through the switch element Q1. The monitoring circuit 4 has a switch element Q4, a resistance element R6, a resistance element R7, a resistance element R8, a resistance element R9, and a switch SW. Further, the monitoring circuit 4 monitors, for example, opening/closing of the door of the vehicle and lighting of an interior light by using the switch SW, and outputs a monitoring signal indicating a monitoring result to the control circuit 2. The switch element Q4 may be, for example, a transistor such as a bipolar transistor. Also, a plurality of monitoring circuits 4 may be provided in the electronic control circuit. The switch SW may be provided inside or outside the monitoring circuit 4.

The circuit configuration of the power supply control circuit 3 will be described.
In FIG. 1, the power supply control circuit 3 is connected between the power supply BT and the control circuit 2, and includes a switch element Q1 that controls power supply and a drive circuit 3a that controls the switch element Q1.

The switch element Q1 is connected between the power source BT and the drive circuit 3a, and controls conduction (ON) and interruption (OFF) based on the output signal of the drive circuit 3a controlled by the control circuit 2. The source (first terminal) of the switch element Q1 is connected to the power supply BT, the drain (second terminal) is connected to the power supply connection terminal (first terminal of the resistance element R6) of the monitoring circuit 4, and the gate (control). The terminal) is connected to the output terminal of the drive circuit 3a (the wiring connecting the collector (second terminal) of the switch element Q3 and the first terminal of the resistance element R5).

The drive circuit 3a is connected between the control circuit 2 and the switch element Q1, the switch element Q2 is connected between the control circuit 2 and the switch element Q3, and the switch element Q3 is connected between the switch element Q2 and the switch element Q1. Is connected in between. The first terminal of the resistance element R1 is connected to the port P1 (control terminal) of the control circuit 2, and the second terminal of the resistance element R1 is the base (control terminal) of the switch element Q2 and the first terminal of the resistance element R2. Connected to. The emitter (first terminal) of the switch element Q2 is connected to the second terminal of the resistance element R2 and the ground, and the collector (second terminal) of the switch element Q2 is connected to the first terminal of the resistance element R3. There is. The second terminal of the resistance element R3 is connected to the base (control terminal) of the switch element Q3 and the first terminal of the resistance element R4. The emitter (first terminal) of the switch element Q3 is connected to the second terminal of the resistance element R4 and the power source BT, and the collector (second terminal) of the switch element Q3 is connected to the first terminal of the resistance element R5 and the switch. It is connected to the gate (control terminal) of the element Q1. The second terminal of the resistance element R5 is connected to the ground.

When the control circuit 2 is in the operation mode, the switch elements Q2 and Q3 are intermittently controlled based on the control signal (high/low signal) output from the port P1 of the control circuit 2. That is, when the control circuit 2 is in the operation mode, the control circuit 2 stops the switch elements Q2 and Q3 (OFF: stops without passing a current through the switch elements Q2 and Q3) and turns on the switch element Q1. At the same time, the switch elements Q2 and Q3 are driven (ON: current is passed through the switch elements Q2 and Q3 to drive), and the switch element Q1 is cut off (OFF). That is, when the control circuit 2 is in the operation mode, the control circuit 2 stops the switch elements Q2 and Q3 (OFF: stops without passing a current through the switch elements Q2 and Q3) and turns on the switch element Q1. The process and the process of driving the switch elements Q2 and Q3 (ON: driving current by flowing the switch elements Q2 and Q3) to cut off (OFF) the switch element Q1 are alternately repeated (first intermittent operation). control).

When the control circuit 2 is normally in the low power mode, the switch elements Q2 and Q3 are controlled based on the control signal (low signal) output from the port P1 of the control circuit 2. That is, when the control circuit 2 is in the normal low power mode, the control circuit 2 stops the switch elements Q2 and Q3 (OFF: stops without supplying a current to the switch elements Q2 and Q3) and turns on the switch element Q1.

The circuit configuration of the monitoring circuit 4 will be described.
The emitter (first terminal) of the switch element Q4 is connected to the drain of the switch element Q1, the first terminal of the resistance element R6, and the first terminal of the resistance element R8. The base (control terminal) of the switch element Q4 is connected to the first terminal of the resistance element R7 and the second terminal of the resistance element R8. The collector of the switch element Q4 (the output terminal of the monitoring circuit 4: the second terminal) is connected to the port P2 (input terminal) of the control circuit 2 and the first terminal of the resistance element R9. The second terminal of the resistance element R9 is connected to the ground. The first terminal of the switch SW is connected to the second terminal of the resistance element R6 and the second terminal of the resistance element R7. One (second terminal) of the switch SW is connected to the ground.

Since the switch SW is normally cut off (OFF) when the control circuit 2 is in the normal low power mode, when the switch element Q1 is conductive (ON), a voltage is applied to the monitoring circuit 4 but a current flows. Absent. However, even when the control circuit 2 is normally in the low power mode, since the voltage is applied to the monitoring circuit 4, it is possible to continue monitoring the state of the switch SW.

In this way, by adding the power supply control circuit 3 to which the switch element Q1 shown in the first embodiment is added to the electronic control circuit 1, when the control circuit 2 is in the operation mode, the power consumption of the electronic control circuit 1 is 2 power consumption W1e (≈W1a), the drive time power consumption W2e (<W2a) during intermittent control of the monitoring circuit 4, and the drive time power consumption W3e during intermittent control of the power supply control circuit 3 Waaa (=W1e+W2e+W3e)<Wa. Since the monitoring circuit 4 and the power supply control circuit 3 are intermittently controlled, the power consumption W2e+W3e is smaller than the power consumption W2a (W2e+W3e<W2a).

Therefore, in the operation mode, the power consumption of the electronic control circuit 1 to which the power supply control circuit 3 is added can be made lower than the power consumption when the power supply control circuit 3 is not added.
Further, when the control circuit 2 is in the normal low power mode, the control circuit 2 does not have to drive the switch elements Q2 and Q3, and the control signal output from the control circuit 2 is changed to a low signal instead of a high signal as in the conventional case. it can. Therefore, the power consumption of the electronic control circuit 1 in the normal low power mode is the power consumption W1f of the control circuit 2 (<W1d: power consumption at high signal output) and the power consumption W2f of the monitoring circuit 4 (≈0 [W]). Power consumption Wsss (=W1f+W2f+W3f)<Ws, which is the sum of power consumption W3f (≈0 [W]) of the power supply control circuit.

Therefore, even in the normal low power mode, the power consumption of the electronic control circuit 1 to which the power supply control circuit 3 is added can be made lower than the power consumption when the power supply control circuit 3 is not added.
Further, since the dark current of the power source BT can be reduced when the switch element Q1 is conductive, when the power source BT is a power storage device such as an auxiliary battery, in the normal low power mode of the control circuit 2, the auxiliary battery The decrease in charge capacity can be delayed.
<Embodiment 2>
In the first embodiment, it has been described that the switch SW shown in FIG. 1 is turned off when the control circuit 2 shown in FIG. 1 is in the normal low power mode (deep sleep mode). However, when the control circuit 2 shifts to the normal low power mode as described in the first embodiment when the switch SW shown in FIG. A control signal (low signal) is output, and the switch elements Q2 and Q3 are stopped (OFF: stopped without passing a current through the switch elements Q2 and Q3) to make the switch element Q1 conductive. Therefore, the switch is performed via the resistor element R6. A current always flows through SW. Therefore, as the resistance element R6, a resistor having a large allowable power must be selected. Then, the size of the resistance element R6 must be increased according to the allowable power of the resistance element R6. In other words, the resistance element R6 has a large size because the resistance element R6 having a large allowable power must be selected in consideration of the maximum current flowing through the resistance element R6.

Further, in the first embodiment, the power consumption is reduced in the operation mode of the control circuit 2 and the normal low power mode, but this is also a measure for downsizing the electronic control circuit 1, and therefore the resistance element R6 If the size remains large, it is against the miniaturization of the electronic control circuit 1.

Therefore, in the second embodiment, the processing of (3) shown below is further added to the processing of (1) and (2) described below in the first embodiment so that the electronic control circuit 1 can be operated even when the switch SW is in the ON fixation failure state. To be able to downsize.
(1) In the operation mode, the control circuit 2 stops the switch element Q2 and the switch element Q3 to bring the switch element Q1 into conduction, and drives the switch element Q2 and the switch element Q3 to switch the switch element Q1. The process of shutting off is repeatedly executed alternately (first intermittent control).
(2) In the low power mode, the control circuit 2 stops the switch element Q2 and the switch element Q3 and makes the switch element Q1 conductive.
(3) When the switch SW is in the ON fixation failure state, the control circuit 2 does not normally shift to the low power mode but enters the fixed low power mode capable of controlling the control signal output from the port P1 of the control circuit 2. The process of shifting and stopping the switch elements Q2 and Q3 to make the switch element Q1 conductive, and the process of driving the switch elements Q2 and Q3 to cut off the switch element Q1 are alternately repeated. (Second intermittent control).

Note that the low power mode during sticking may be, for example, a mode in which the normal low power mode periodically shifts to the operation mode, or the control circuit 2 can reduce power consumption compared to the operation mode, so that the port P1 of the control circuit 2 Any mode can be used as long as it can control the output control signal.

Further, the conduction time and the interruption time (duty) of the switch element Q1 in the first intermittent control of the above (1) are determined by the drive start cycle and the driving time of the monitoring circuit 4, but the second intermittent of the above (3). The conduction time and the cutoff time (duty) of the switch element Q1 in the control are determined by the amount of current intermittently supplied to the resistance element R6 when the switch SW is in the on-fixation failure state. However, the duty in the second intermittent control of (3) above may be the same as the duty in the first intermittent control of (1) above. The reason is that the power consumption can be reduced only by intermittently controlling the switch element Q1.

As described above, by adding the process (3) to the processes (1) and (2) of the first embodiment, the current intermittently flows through the resistance element R6, and thus the current flowing through the resistance element R6 can be reduced. As a result, a resistance element having a small allowable power can be selected, and the size of the resistance element R6 can be reduced. Therefore, the size of the electronic control circuit 1 can be reduced.

The second embodiment will be described with reference to FIG.
FIG. 2 is a diagram illustrating an example of the electronic control circuit 201 according to the second embodiment. The electronic control circuit 201 includes a control circuit 2, a power supply control circuit 3, and a monitoring circuit 202 (202a, 202b). The control circuit 2 and the power supply control circuit 3 of the electronic control circuit 201 are, for example, an EUC (Electronic Control Unit) mounted on a vehicle.

The monitoring circuit 202 includes a resistance element R6 (R6a, R6b: first resistance element) and a resistance element R7 (R7a, R7b: second resistance element). The resistance elements R6 and R7 limit the current flowing from the power source BT to the device 203 and the port P2 (input terminal) and the port P3 (input terminal) of the control circuit 2. The device 203 is, for example, a vehicle side installed in a vehicle. A lid box containing a charging inlet may be considered. Further, the switches SWa and SWb provided in the device 203 are momentary switches and the like, for example, a momentary switch that is pressed when the vehicle-side charging inlet provided in the lid box and the charging gun are connected, or A momentary switch that is pressed when the lid of the lid box is opened can be considered.

The difference between the electronic control circuit 201 shown in FIG. 2 of the second embodiment and the electronic control circuit 1 shown in FIG. 1 of the first embodiment is that the monitoring circuit 4 of FIG. Although the resistance elements R8 and R9 are provided, in the monitoring circuit 202 (202a, 202b) of FIG. 2, the switch SW (SWa, SWb) is provided in the device 203 different from the electronic control circuit 201. ..

In the monitoring circuit 202 of FIG. 2, the voltage level conversion circuit (switch element Q4, resistance elements R8, R9) corresponding to the switch SW is provided in the control circuit 2, and therefore is not shown in FIG. When the voltage level conversion is not necessary, the control circuit 2 may not be provided with the voltage level conversion circuit.

The circuit configurations of the electronic control circuit 201 and the device 203 of the second embodiment will be described.
The circuit configuration of the power supply control circuit 3 of FIG. 2 is the same as that of the power supply control circuit 3 of FIG. The drain (second terminal) of the switch element Q1 is connected to the power supply connection terminal of the monitoring circuit 202a (first terminal of the resistance element R6a) and the power supply connection terminal of the monitoring circuit 202b (first terminal of the resistance element R6b). Has been done. The port P2 (input terminal) of the control circuit 2 is connected to the first terminal (output terminal) of the resistance element R7a. The port P3 (input terminal) of the control circuit 2 is connected to the first terminal (output terminal) of the resistance element R7b. The second terminal of the resistance element R6a is connected to the first terminal of the switch SWa of the device 203 and the second terminal of the resistance element R7a. One (second terminal) of the switch SWa is connected to the ground. The second terminal of the resistance element R6b is connected to the first terminal of the switch SWb of the device 203 and the second terminal of the resistance element R7b. One (second terminal) of the switch SWb is connected to the ground.

The control circuit 2 of the second embodiment will be described.
When the switch SWa or/and the switch SWb are in the stuck-on failure state, the control circuit 2 does not normally shift to the low power mode but shifts to the low power mode at the time of stuck, and the control signal from the port P1 of the control circuit 2 Output (high/low signal).

When the power supply control circuit 3 acquires the control signal output from the port P1 of the control circuit 2, the power supply control circuit 3 stops the switch element Q2 and the switch element Q3 (OFF: no current flows through the switch elements Q2 and Q3). Stop) to turn on the switch element Q1 and drive the switch element Q2 and the switch element Q3 (on: drive current by passing a current through the switch elements Q2 and Q3) to cut off the switch element Q1 ( The process of turning off) is alternately and repeatedly executed (second intermittent control).

Then, since the switch element Q1 is intermittently controlled, even when the switch SWa or SWb is in the ON-fixed fault state, an intermittently controlled current flows through the resistor element R6 and the switch SW (because the current value is small). Since a resistance element having a small allowable power can be adopted as R6, the size of the resistance element R6 can be reduced. As a result, the electronic control circuit 1 can be downsized.

Further, when the plurality of resistance elements R6a and R6b are connected to the drain of the switch element Q1, the sizes of the resistance elements R6a and R6b corresponding to the switches SWa and SWb can be reduced, respectively, so that the electronic control circuit 1 is further reduced. It can be miniaturized.

The operation of the second embodiment will be described.
FIG. 3 is a diagram illustrating an example of the operation of the electronic control circuit 201 according to the second embodiment. In step S1, the control circuit 2 acquires each of the monitoring signals output from the monitoring circuits 202a and 202b to the ports P2 and P3 of the control circuit 2.

In step S2, the control circuit 2 determines whether or not the switch SW is in the on-fixing failure state. If the switch SW is in the on-fixing failure state (S2: Yes), the process proceeds to step S3 and is not the on-fixing failure state. In that case (S2: No), the process proceeds to step S4. In the example of FIG. 2, assuming that the switch SWa is in the stuck-on failure state, the monitoring signal acquired at the port P2 of the control circuit 2 continues to be in the low state.

In the case of the electronic control circuit 1 shown in FIG. 2, it is determined whether the switch SW is in the on-fixing failure state if the switch SW is in the on-fixing failure state when the low state of the monitoring signal continues for a predetermined time or longer. It is determined to be in the state. The predetermined time is a time at which the switch SW can be considered to be in the on-fixation failure state, and is determined by, for example, an experiment or a simulation, and is stored in a storage unit (not shown) provided inside or outside the control circuit 2.

In step S3, when the switch SW is in the on-fixing failure state, the control circuit 2 stores the sticking information indicating that the switch SW is in the on-fixing failure state in the storage unit. For example, in the example of FIG. 2, if the switch SWa is in the on-fixing failure state, the control circuit 2 stores the sticking information indicating that the switch SWa is in the on-fixing failure state in the storage unit. Even when the switch SWb is in the stuck-on failure state, the control circuit 2 similarly stores the stuck information in the storage unit.

In step S4, when the switch SW is not in the on-fixing failure state, the control circuit 2 stores the sticking information indicating that the switch SW is not in the on-fixing failure state in the storage unit. For example, in the example of FIG. 2, assuming that the switch SWa is not in the on-fixing failure state, the control circuit 2 stores the sticking information indicating that the switch SWa is not in the on-fixing failure state in the storage unit. Even when the switch SWb is not in the on-fixation failure state, the control circuit 2 similarly stores the fixation information in the storage unit.

In step S5, the control circuit 2 determines whether the low power mode transition condition is satisfied. If the low power mode shift condition is satisfied (S5: Yes), the process proceeds to step S6, and if the low power mode shift condition is not satisfied (S5: No), the process proceeds to step S1. The low power mode shift condition is when the control circuit 2 described in the first embodiment shifts to the normal low power mode, or when the control circuit 2 detects that the switch SW is in the stuck-on failure state.

The processing of steps S1 to S5 (broken line frame) is a part of the processing of the operation mode. In other words, in steps S1 to S5, the control circuit 2 performs the processing (1) of the above (first intermittent operation). This is a process that is executed together with (control).

In step S6, when the control circuit 2 refers to the sticking information stored in the storage unit in step S3 or step S4, and the sticking information indicates that the switch SW is in the ON sticking failure state (S6: Yes). In step S7, the process proceeds to step S7. If the sticking information indicates that the switch SW is not in the ON sticking failure state (S6: No), the process proceeds to step S8.

In step S7, the control circuit 2 executes the above process (3). That is, a process of shifting to the low power mode at the time of fixation, processing of stopping the switch elements Q2 and Q3 to make the switch elements Q1 conductive, and driving the switch elements Q2 and Q3 to cut off the switch elements Q1. The processing and the processing are alternately and repeatedly executed (second intermittent control).

In step S8, the control circuit 2 executes the above process (2). That is, the switch element Q2 and the switch element Q3 are stopped and the switch element Q1 is made conductive.
When the processes of steps S7 and S8 are completed, the control circuit 2 shifts to the operation mode (wakes up) in step S9, and thus waits until the wakeup condition is satisfied. The control circuit 2 proceeds to step S1 when the wakeup condition is satisfied (S9: Yes), and waits at step S9 when the wakeup condition is not satisfied (S9: No).

As described above, according to the second embodiment, as described in the first embodiment, it is possible to reduce the power consumption of the electronic control circuit 1 even in the operation mode and the normal low power mode, and the switch element Q1 becomes conductive. In this case, the dark current of the power source BT can be reduced.

Furthermore, according to the second embodiment, even when the switch SW is in the ON-fixed fault state, the low-power mode is set at the time of sticking, and the first switch element Q1 is intermittently controlled, so that the resistor element R6 and the switch SW are intermittently connected. Since a different current flows (because the current flowing through the resistance element R6 is small), a resistance element having a small allowable power can be selected as the resistance element R6. As a result, the resistance element R6 can be downsized, and the electronic control circuit 1 can be downsized.

Further, when there are a plurality of switches SWa and SWb, the resistance elements R6a and R6b corresponding to the switches SWa and SWb can be reduced in size, respectively, so that the electronic control circuit 1 can be further downsized.

Further, the present invention is not limited to the above embodiments, and various improvements and changes can be made without departing from the gist of the present invention.

1, 201 electronic control circuit 2 control circuit 3 power supply control circuit 3a drive circuit 4, 202 monitoring circuit 202a, 202b monitoring circuit 203 device BT power supply Q1, Q2, Q3, Q4 switch elements R1, R2, R3, R4, R5, R6 , R7, R8, R9 resistance element R6a, R6b, R7a, R7b resistance element SW switch SWa, SWb switch

Claims (4)

The power supply control circuit connected between the power supply and the control circuit,
A first switch element for controlling the power supply,
A drive circuit for controlling the first switch element,
The drive circuit is
A second switch element and a third switch element,
The control circuit is
In the case of a normal low power mode, the second switch element and the third switch element are stopped to conduct the first switch element,
In the operation mode, intermittently controlling the second switching element and the third switching element,
The intermittent control includes a process of stopping the second switch element and the third switch element to bring the first switch element into conduction, and the second switch element and the third switch element. A process of driving and cutting off the first switch element is repeatedly executed alternately.
An electronic control circuit characterized by the above. The electronic control circuit according to claim 1, wherein
The control terminal of the control circuit and the input terminal of the drive circuit are connected,
The control terminal of the first switch element and the output terminal of the drive circuit are connected,
The first terminal of the first switch element and the power source are connected,
The second terminal of the first switch element and the power supply connection terminal of the monitoring circuit are connected,
One of the switches provided inside or outside the monitoring circuit is connected to the ground,
The output terminal of the monitoring circuit and the input terminal of the control circuit are connected,
The switch is in a cutoff state when the control circuit is in the normal low power mode,
An electronic control circuit characterized by the above. An electronic control circuit having a control circuit, a power supply control circuit, and a monitoring circuit,
The power control circuit,
Connected between the power supply and the control circuit,
A first switch element for controlling the power supply,
A drive circuit for controlling the first switch element by using a second switch element and a third switch element,
The monitoring circuit is
Monitor the state of the device using a switch provided in the device different from the electronic control circuit,
A first resistance element for limiting a current flowing from the power source to the input terminal of the switch and the control circuit through the first switch element,
The control circuit is
In the operation mode, a process of stopping the second switch element and the third switch element to bring the first switch element into conduction, and the second switch element and the third switch element, A process of driving and cutting off the first switching element is alternately and repeatedly executed,
In the case of a normal low power mode, the second switch element and the third switch element are stopped to conduct the first switch element,
If the switch is in the conduction fixation failure state, transition to a low power mode at the time of fixation, a process of stopping the second switch element and the third switch element to make the first switch element conductive, A process of driving the second switch element and the third switch element to interrupt the first switch element is alternately repeated.
An electronic control circuit characterized by the above. The electronic control circuit according to claim 3, wherein
The control terminal of the control circuit and the input terminal of the drive circuit are connected,
The control terminal of the first switch element and the output terminal of the drive circuit are connected,
The first terminal of the first switch element and the power source are connected,
The second terminal of the first switch element and the first terminal of the first resistance element are connected,
The first terminal of the second resistance element provided in the monitoring circuit and the input terminal of the control circuit are connected,
The second terminal of the first resistance element, the second terminal of the second resistance element and the first terminal of the switch are connected,
The second terminal of the switch and the ground are connected,
An electronic control circuit characterized by the above.

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