Power supply control apparatus

Abstract

A power supply control apparatus (100, 200, 300, 400), comprising: a power supply control unit (110), which comprises a power supply control switch (Q1), a first voltage division resistor (R1) and a second voltage division resistor (R2); and a driving unit (120), which is used for driving the turning on and turning off of the power supply control switch (Q1), wherein a power source (Vcc) is connected to a power supply output end by means of the first voltage division resistor (R1), the power supply output end is connected to a reference potential point by means of the second voltage division resistor (R2), the power supply control switch (Q1) is connected to the first voltage division resistor (R1) in parallel, and when the power supply control switch (Q1) is turned off, the power supply output end outputs a first power supply voltage, and when the power supply control switch (Q1) is turned on, the power supply output end outputs a second power supply voltage, the second power supply voltage being greater than the first power supply voltage. By means of the power supply control apparatus (100, 200, 300, 400), a central controller can control the power supply to sensors or other components in a vehicle by means of small signals, and can detect a power supply state.

Description

Power supply control device TECHNICAL FIELD

[0001] The present disclosure relates to a power supply control device. BACKGROUND

[0002] A large number of sensors are arranged in a vehicle. The control unit of the vehicle communicates with the sensors on the one hand to control the sensors and to obtain data from the sensors. On the other hand, the control unit of the vehicle also needs to control the power supply to the sensors. SUMMARY

[0003] The present disclosure provides a power supply control device, by which a central controller can control the power supply to sensors or other components in a vehicle by a small signal, and the state of the power supply can be detected.

[0004] The present disclosure provides a power supply control device, comprising: a power supply control unit comprising a power supply control switch, a first voltage dividing resistor and a second voltage dividing resistor; a driving unit for driving the turn-on and turn-off of the power supply control switch; wherein a power supply is connected to a power supply output terminal through the first voltage dividing resistor, the power supply output terminal is connected to a reference potential point through the second voltage dividing resistor, the power supply control switch is connected in parallel with the first voltage dividing resistor, and wherein the power supply output terminal outputs a first power supply voltage when the power supply control switch is turned off, and outputs a second power supply voltage when the power supply control switch is turned on, wherein the second power supply voltage is greater than the first power supply voltage.

[0005] In an embodiment according to the present disclosure, the driving unit comprises a driving switch, a first biasing element and a second biasing element, wherein the power supply control switch and the driving switch are configured as electronic switches, the first biasing element is arranged between the emitter or drain and the control electrode of the power supply control switch, the second biasing element and the driving switch form a series circuit arranged between the control electrode of the power supply control switch and the reference potential point, and wherein the turn-on and turn-off of the power supply control switch are controlled by the turn-on and turn-off of the driving switch.

[0006] In an embodiment according to the present disclosure, the power supply control switch is configured as a PNP transistor, the driving switch is configured as an NPN transistor, and wherein the turn-off of the driving switch drives the power supply control switch to turn off, and the turn-on of the driving switch drives the power supply control switch to turn on.

[0007] In an embodiment according to the present disclosure, the first biasing element and the second biasing element are configured as resistors.

[0008] In an embodiment according to the present disclosure, the first biasing element is configured as at least one diode for realizing constant current output when the power supply control switch is on, and the second biasing element is configured as a resistor.

[0009] In an embodiment according to the present disclosure, the power supply control unit further comprises a current limiting resistor connected in series with the power supply control switch.

[0010] In an embodiment according to the present disclosure, the power supply control unit further comprises a third voltage dividing resistor, and the power supply output end is connected to the reference potential point through the second voltage dividing resistor and the third voltage dividing resistor, forming a power supply voltage detection end between the second voltage dividing resistor and the third voltage dividing resistor.

[0011] In an embodiment according to the present disclosure, a filter capacitor is arranged at the power supply voltage detection end.

[0012] In an embodiment according to the present disclosure, a voltage clamping diode is arranged at the power supply voltage detection end.

[0013] In an embodiment according to the present disclosure, the power supply control device further comprises a reverse polarity protection diode, wherein the reverse polarity protection diode is arranged between a power source and the power supply control unit. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following will briefly introduce the drawings needed to be used in the description of the embodiments. Obviously, the drawings in the following description are only some example embodiments of the present disclosure, and other embodiments can also be obtained by those of ordinary skill in the art without creative labor on the basis of these embodiments.

[0015] FIG. 1 shows a schematic circuit diagram of a power supply control device according to an embodiment of the present disclosure,

[0016] FIG. 2 shows a schematic circuit diagram of a power supply control device according to another embodiment of the present disclosure,

[0017] FIG. 3 shows a schematic circuit diagram of a power supply control device according to another embodiment of the present disclosure, and

[0018] FIG. 4 shows a schematic circuit diagram of a power supply control device according to another embodiment of the present disclosure. DETAILED DESCRIPTION

[0019] In order to make the objectives, technical solutions, and advantages of the present disclosure clearer, the following will describe the example embodiments according to the present disclosure in detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments of the present disclosure, and it should be understood that the present disclosure is not limited to the example embodiments described herein.

[0020] In the present specification and drawings, substantially identical or similar method steps and elements are denoted by identical or similar reference numerals, and repeated descriptions of these method steps and elements will be omitted. Meanwhile, in the description of the present disclosure, the terms "first", "second", and the like are only used to distinguish descriptions, and cannot be understood as indicating or implying relative importance or sequence. In the embodiments of the present disclosure, unless explicitly stated otherwise, "connection" does not mean "direct connection" or "direct contact", but only requires electrical communication.

[0021] A large number of sensors are arranged in a vehicle. The control unit of the vehicle communicates with the sensors on the one hand to control the sensors and obtain data from the sensors. On the other hand, the control unit also needs to control the power supply to the sensors. The control unit of the vehicle can be a central controller, a microcontroller (MCU), a domain controller (DCU), or an electronic controller (ECU), for example. The power supply control of other components such as sensors by the control unit of the vehicle is achieved by a power supply control device.

[0022] The present disclosure provides a power supply control device in which the output voltage Vout, i.e. the power supply Vcc to the load, can be controlled by an enable signal Venable. Fig. 1 shows a schematic diagram of a power supply control device 100 according to the present disclosure. The power supply control device 100 comprises a power supply control unit 110 and a drive unit 120. The power supply control unit 110 comprises a power supply control switch Q1, a first voltage dividing resistor R1 and a second voltage dividing resistor R2. The power supply Vcc is connected to a power supply output via the first voltage dividing resistor R1, and the power supply output is connected to a reference potential point, which is ground in the present disclosure, but can also be set to other reference potential points. The power supply control switch Q1 is connected in parallel with the first voltage dividing resistor R1.

[0023] The drive unit 120 is used to drive the turn-on and turn-off of the power supply control switch Q1. In the case where the power supply control switch Q1 is turned off, the power supply output outputs a first power supply voltage, and the output voltage Vout of the power supply output depends on the voltage division between the first voltage dividing resistor R1 and the second voltage dividing resistor R2, i.e. Vcc*R2(R1+R2). In the case where the power supply control switch Q2 is turned on, the power supply output outputs a second power supply voltage, for example Vcc, wherein the second power supply voltage is greater than the first power supply voltage.

[0024] In embodiments of the present disclosure, the output voltage Vout of the power supply output also depends on the load. In the case that the power supply control switch Q1 is off, for the case of no load or load is disconnected, the output voltage Vout is equal to the voltage on the second voltage dividing resistor R2. If the first voltage dividing resistor R1 is equal to the second voltage dividing resistor R2, the output voltage Vout is equal to Vcc / 2. For the case of normal load connection, the output voltage Vout is approximately equal to 0V, since the impedance of the load is much smaller than the voltage dividing resistors R1 or R2. For the case of load shorted to ground, the output voltage Vout is approximately equal to 0V.

[0025] In the case that the power supply control switch Q1 is on, for the case of no load or load is disconnected, the output voltage Vout is equal to Vcc. For the case of normal load connection, the output voltage Vout is approximately equal to Vcc (considering the on-state voltage drop of the power supply control switch Q1, and the current limiting resistor R5 if present, the output voltage Vout is less than Vcc). For the case of load shorted to ground, the output voltage Vout is approximately equal to 0V.

[0026] In embodiments according to the present disclosure, the drive unit 120 may, for example, comprise a drive switch Q2, a first biasing element and a second biasing element. In the embodiment shown in Fig. 1, the first biasing element and the second biasing element are configured as resistors R3 and R4, respectively. The power supply control switch Q1 and the drive switch Q2 may, for example, be configured as electronic switches such as transistors. In embodiments of the present disclosure, the power supply control switch Q1 may, for example, be configured as a PNP transistor, and the drive switch Q2 may, for example, be configured as an NPN transistor. The first biasing resistor R3 is arranged between the emitter and the control (base) of the power supply control switch Q1. The series circuit of the second biasing element R4 and the drive switch Q2 is arranged between the control (base) of the power supply control switch Q1 and the reference potential point. The on and off of the power supply control switch Q1 is controlled by the on and off of the drive switch Q2. The on and off of the drive switch Q2 is controlled by the enable signal Venable applied to the control (base) of the drive switch Q2. The enable signal Venable may, for example, be issued by a central controller, a domain controller or an electronic controller.

[0027] In another embodiment, the power supply control switch Q1 and the drive switch Q2 may, for example, be configured as other electronic switches such as MOSFET and IGBT. The first biasing resistor R3 is arranged between the drain and the control (gate) of the power supply control switch Q1. The series circuit of the second biasing element R4 and the drive switch Q2 is arranged between the control (gate) of the power supply control switch Q1 and ground.

[0028] The turn-on and turn-off of the drive switch Q2 is controlled by an enable signal Venable applied to the control electrode of the drive switch Q2. When the enable signal Venable is not present, the drive switch Q2 is turned off, and no voltage is present on the first biasing resistor R3, and the power supply control switch Q1 is turned off. When the enable signal Venable is present, the drive switch Q2 is turned on, and a voltage drop is present on the first biasing resistor R3, and the voltage U EB greater than the turn-on voltage, the power supply control switch Q1 is turned on.

[0029] In an embodiment according to the present disclosure, the enable signal Venable can be a PWM signal, for example. The PWM signal controls the turn-on and turn-off of the drive switch Q2, and in turn controls the output voltage Vout or the supply voltage of the load, so as to achieve the control of the supply of the load by a small signal.

[0030] In an embodiment according to the present disclosure, the power supply control unit 110 comprises a current-limiting resistor, which is shown by resistor R5 in FIGS. 1 to 4. The current-limiting resistor R5 is connected in series with the power supply control switch Q1, and is used to limit the output current.

[0031] FIG. 2 shows a schematic circuit diagram of a power supply control device 200 according to another embodiment of the present disclosure. In an embodiment according to the present disclosure, the first biasing element can be configured as at least one diode, for example. In the embodiment shown in FIG. 2, the first biasing element is configured as two diodes D2 and D3 connected in series. The second biasing element is still configured as the resistor R4. When the drive switch Q2 is turned on, the turn-on voltage drop of the two diodes D2 and D3 connected in series is fixed, for example, at 0.7V*2 = 1.4V. The voltage U EB is limited to 1.4V. Therefore, the current flowing through the power supply control switch Q1 is I = (U EB -0.7V) / R5, where 0.7V is the voltage drop of the emitter junction of the power supply control switch Q1. By this design, a constant current output at the power supply output end when the drive switch Q2 is turned on can be achieved.

[0032] Fig. 3 shows a schematic circuit diagram of a power supply control device 300 according to another embodiment of the present disclosure. Compared with the power supply control device 100 shown in Fig. 1, a third voltage dividing resistor R6 is additionally arranged in the power supply control device 300. Therefore, the power supply output end is connected to the reference potential point through the second voltage dividing resistor R2 and the third voltage dividing resistor R6. The power supply voltage detection end is formed between the second voltage dividing resistor R2 and the third voltage dividing resistor R6. The output voltage (detection voltage) Vdet of the power supply voltage detection end is proportional to the output voltage Vout of the power supply output end, i.e. Vdet = Vout * R6 / (R2 + R6). By setting the size and proportion of the second voltage dividing resistor R2 and the third voltage dividing resistor R6, the detection voltage Vdet can be far less than the output voltage Vout. By detecting the smaller detection voltage Vdet, the monitoring of the output voltage Vout of the power supply output end can be achieved. The detection voltage Vdet can be fed back to the central controller, domain controller or electronic controller for issuing the enable signal Venable. These controllers can adjust the output voltage Vout in a PWM manner according to the feedback signal.

[0033] As mentioned before, the output voltage Vout of the power supply output end depends on the switching state of the power supply control switch Q1 on the one hand and on the state of the load on the other hand. Therefore, the state of the load can be determined according to the output voltage Vout or the detection voltage Vdet, which includes: normal connection, no connection (open circuit) and short circuit. The relationship between the output voltage Vout or the detection voltage Vdet and the state of the load is shown in the following table:

[0034] Fig. 4 shows a schematic circuit diagram of a power supply control device 400 according to another embodiment of the present disclosure. The power supply control device 400 shown in Fig. 4 is a preferred embodiment of the present disclosure. Compared with the embodiment shown in Fig. 3, additional components are further included in the power supply control device 400. These components can be implemented individually or in combination with each other.

[0035] In the embodiment shown in Fig. 4, the power supply control device 400 can further include a reverse polarity protection diode D1. The reverse polarity protection diode D1 is arranged between the power supply Vcc and the power supply control unit 110, for limiting the current direction.

[0036] In this embodiment, a filter capacitor C1 can also be arranged at the power supply voltage detection end. The filter capacitor C1 is arranged between the power supply voltage detection end and the ground, and can be used to filter out high-frequency noise.

[0037] In this embodiment, a voltage clamping diode can also be arranged at the power supply voltage detection terminal. As shown in FIG. 4, voltage clamping diodes D2 and D3 are arranged. Voltage clamping diode D2 is arranged between the power supply Vcc and the power supply voltage detection terminal, and voltage clamping diode D3 is arranged between the power supply voltage detection terminal and the ground. When an excessively large positive or negative voltage occurs at the power supply voltage detection terminal, the excessively large voltage can cause the conduction of voltage clamping diode D2 or D3, thereby avoiding the influence or damage of the excessively large voltage on the power supply voltage detection terminal.

[0038] The block diagrams of the circuits, units, devices, apparatuses, devices, systems involved in the present disclosure are only exemplary examples and are not intended to require or imply the connection, arrangement, configuration as shown in the block diagrams. As those skilled in the art will recognize, these circuits, units, devices, apparatuses, devices, systems can be connected, arranged, configured in any way as long as the desired purpose can be achieved. The circuits, units, devices, apparatuses involved in the present disclosure can be implemented in any suitable way, for example, in the form of application specific integrated circuits, field programmable gate arrays (FPGA), etc., or in the form of general purpose processors combined with programs.

[0039] Those skilled in the art should understand that the above specific embodiments are only examples and are not limiting, and various modifications, combinations, partial combinations and replacements of the embodiments of the present disclosure can be made according to design requirements and other factors, as long as they are within the scope of the appended claims or their equivalents, i.e. belong to the scope of protection of the present disclosure.

Claims

1. A power supply control device, comprising: a power supply control unit including a power supply control switch, a first voltage dividing resistor and a second voltage dividing resistor; a driving unit for driving the power supply control switch to turn on and off; wherein a power supply is connected to a power supply output terminal through the first voltage dividing resistor, the power supply output terminal is connected to a reference potential point through the second voltage dividing resistor, the power supply control switch is connected in parallel with the first voltage dividing resistor, and wherein the power supply output terminal outputs a first power supply voltage when the power supply control switch is off, and outputs a second power supply voltage when the power supply control switch is on, wherein the second power supply voltage is greater than the first power supply voltage. 2.The power supply control device according to claim 1, wherein the driving unit includes a driving switch, a first biasing element and a second biasing element, wherein the power supply control switch and the driving switch are configured as electronic switches, the first biasing element is arranged between an emitter or a drain and a control electrode of the power supply control switch, a series circuit composed of the second biasing element and the driving switch is arranged between the control electrode of the power supply control switch and the reference potential point, and wherein the power supply control switch is controlled to turn on and off by turning on and off of the driving switch. 3.The power supply control device according to claim 2, wherein the power supply control switch is configured as a PNP transistor, the driving switch is configured as an NPN transistor, and wherein the driving switch is turned off to drive the power supply control switch to be off, and the driving switch is turned on to drive the power supply control switch to be on. 4.The power supply control device according to claim 2, wherein the first biasing element and the second biasing element are configured as resistors. 5.The power supply control device according to claim 2, wherein the first biasing element is configured as at least one diode for realizing constant current output when the power supply control switch is on, and the second biasing element is configured as a resistor. 6.The power supply control device according to claim 1, wherein the power supply control unit further includes a current limiting resistor connected in series with the power supply control switch. 7.The power supply control device according to claim 1, wherein the power supply control unit further includes a third voltage dividing resistor, and the power supply output terminal is connected to the reference potential point through the second voltage dividing resistor and the third voltage dividing resistor, and a power supply voltage detection terminal is formed between the second voltage dividing resistor and the third voltage dividing resistor. 8.The power supply control device according to claim 7, wherein, a filter capacitor is arranged at the power supply voltage detection terminal. 9.The power supply control device according to claim 7, wherein a voltage clamping diode is arranged at the power supply voltage detection terminal.

10. The power supply control device of claim 1, further comprising a reverse polarity protection diode, wherein, the reverse polarity protection diode is arranged between a power supply and the power supply control unit.

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