Domain-control automatic circuit breaking circuit

Abstract

The invention discloses a domain-control automatic circuit breaking circuit, which comprises a power supply input end, a driving output end, a grounding end, an under-voltage detection circuit and an MOS (Metal Oxide Semiconductor) driving chip, wherein the under-voltage detection circuit comprises a first resistance voltage division circuit and a reset circuit; the power supply input end is connected with the MOS driving chip and supplies power to the MOS driving chip; the first resistor voltage division circuit is connected with the input end of the reset circuit; the reset circuit has a hysteresis characteristic, outputs a low-level signal when detecting that the input voltage is under-voltage, and outputs a high-level signal when detecting that the input voltage is recovered; the output end of the reset circuit is connected with the input end of the MOS driving chip, and the output of the MOS driving chip is started and closed. The domain-control automatic circuit breaking circuit belongs to pure hardware design, the stability of the product is more reliable than that of a software and hardware combination scheme, the product is not limited by program control, and invalid turn-off caused by dead halt is avoided; moreover, the circuit is simple, is low in power consumption, and is smaller in overall design size.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit breaking circuits, and in particular to a domain-controlled automatic circuit breaking circuit. Background Art

[0002] With the popularization of new energy sources, the number of black technologies for vehicle body electricity consumption continues to increase. Some convenient black technologies need to be executed after the vehicle enters sleep mode, such as remote preheating of seats and steering wheels, remote vehicle start, and remote monitoring of recorders. These modules that can be turned on remotely will still work silently after the vehicle enters sleep mode, but the power consumption will be reduced. However, when so many modules work at the same time, the superposition will also increase the static power consumption of the entire vehicle. Therefore, it is very important to prioritize the protection of key modules according to the primary and secondary relationships while ensuring that the vehicle body battery is not depleted.

[0003] Many modules now use MCU to collect voltage for monitoring, and shut down the functional modules when the voltage is lower than a certain level. The operation of MCU also requires the support of current. If it enters sleep mode to reduce power consumption, and the voltage cannot be monitored, the standby power consumption will be too high. Summary of the invention

[0004] The present invention aims to provide a small-volume, low-power, pure hardware domain-controlled automatic circuit breaker circuit to solve the above-mentioned technical problems. The technical solution is as follows:

[0005] A domain-controlled automatic circuit-breaking circuit comprises a power input terminal, a drive output terminal and a ground terminal, as well as an undervoltage detection circuit and a MOS drive chip;

[0006] The undervoltage detection circuit includes a first resistor voltage divider circuit and a reset circuit;

[0007] The power input terminal is connected to the MOS driver chip to supply power to the MOS driver chip; and is connected to the input terminal of the reset circuit through a first resistor voltage divider circuit;

[0008] The reset circuit has a hysteresis characteristic, and outputs a low level signal when it detects that the input voltage is lower than the lower hysteresis threshold, and outputs a high level signal when it detects that the input voltage is higher than the upper hysteresis threshold;

[0009] The output end of the reset circuit is connected to the input end of the MOS driver chip to start and shut down the output of the MOS driver chip.

[0010] Furthermore, the reset circuit is implemented by a reset chip with a low-side output.

[0011] Furthermore, the domain-controlled automatic disconnection circuit also includes an RC delay circuit, and the RC delay circuit is connected in series between the output end of the reset circuit and the input end of the MOS driver chip.

[0012] Furthermore, the RC delay circuit includes a plurality of chip capacitors connected in parallel.

[0013] Furthermore, the domain-controlled automatic circuit breaker circuit also includes an enabling circuit, a first diode, and a second diode; the output end of the reset circuit is connected to the anode of the first diode, and the cathode of the first diode is connected to the input end of the RC delay circuit; the enabling circuit includes a control end, and a second resistor divider circuit, the control end is connected to the input end of the second resistor divider circuit, the output end of the second resistor divider circuit is connected to the anode of the second diode, and the cathode of the second diode is connected to the input end of the RC delay circuit.

[0014] Furthermore, the first diode and the second diode are two diode units of a common cathode diode.

[0015] Furthermore, a first fuse is included between the control terminal and the second resistor voltage divider circuit.

[0016] Furthermore, the MOS driver chip is a high-side driver MOS chip.

[0017] Furthermore, the output end of the MOS driver chip is grounded through a transient voltage suppression device.

[0018] Furthermore, a first fuse is provided between the power input terminal and the MOS driver chip.

[0019] The present invention achieves the following technical effects:

[0020] This domain control automatic circuit breaker is a pure hardware design. The stability of the product is more reliable than the combination of software and hardware. It is not limited by program control and will not cause invalid shutdown due to a freeze.

[0021] The circuit is simple, the power consumption is low, and the overall design volume is smaller. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a principle block diagram of the domain-controlled automatic circuit-breaking circuit of the present invention;

[0023] Figure 2 It is a circuit diagram of an embodiment of a domain-controlled automatic circuit-breaking circuit of the present invention. DETAILED DESCRIPTION

[0024] To further illustrate the various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, a person of ordinary skill in the art should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0025] The present invention will now be further described with reference to the accompanying drawings and specific implementation methods.

[0026] To further illustrate the various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, a person of ordinary skill in the art should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0027] Embodiment 1:

[0028] like Figure 1 As shown, the present invention provides a schematic diagram of a domain-controlled automatic circuit-breaking circuit. The domain-controlled automatic circuit-breaking circuit is composed of a reset chip U1, a MOS driver chip U2, and resistors R1, R2, etc., including lead-out terminals such as a power input terminal, a control terminal, a drive output terminal, and a ground terminal. In this embodiment, the input voltage of the reset chip U1 is usually 3.3V or 5V, and the power supply voltage of the MOS driver chip U2 is 12V or 24V, which is directly powered by the power supply. Resistors R1 and R2 form a voltage divider circuit. The power input terminal of the domain-controlled automatic circuit-breaking circuit is connected to the power supply externally, and is connected to the input terminal of the reset chip U1 through the voltage divider circuit internally to power the reset chip U1. The output terminal of the reset chip U1 is connected to the input terminal of the MOS driver chip U2. The function of the reset chip U1 is to detect abnormal voltage. When the power supply voltage is abnormal, the reset chip U1 will continue to output a low level and turn off the output of the MOS driver chip U2. The MOS driver chip U2 can use a high-side MOS, such as the BTS7010 of the Infineon BTT series and other MOS driver chips, which can be used as a driving switch for high-power MOSFET and IGBT.

[0029] Preferably, the reset chip U1 is a low-side output reset chip, such as IMP809T, etc., which automatically outputs a low-level reset signal when the input voltage is abnormal.

[0030] The reset chip U1 is a chip with hysteresis characteristics. Assuming that when the voltage drops to the set value such as V1, the output is low level, but the voltage must be higher than V1+0.3V before U1 can restore to high level. Prevent the MOS driver chip U2 from switching frequently when the level is at the set critical voltage, thereby damaging the back-end components.

[0031] Embodiment 2:

[0032] like Figure 2 As shown, the present invention provides an embodiment of a domain-controlled automatic circuit-breaking circuit for a vehicle. The domain-controlled automatic circuit-breaking circuit adopts a design of separating the power input terminal and the control terminal, including lead terminals such as the power input terminal, the control terminal, the drive output terminal and the ground terminal. Among them, the power input terminal is connected to the positive electrode B+ of the battery, represented by B+; the control terminal is connected to the ACC signal line, represented by ACC; the ground terminal is connected to the reference ground, represented by GND; the drive output terminal is connected to the subsequent device (such as power switches such as high-power MOSFET and IGBT), represented by OUT.

[0033] The power input terminal B+ is connected to the power input terminal VS of the MOS driver chip U2 through the diode D2 and the fuse F2, and is marked as the power signal B+2. In the branch circuit, the power signal B+2 passes through the voltage divider circuit composed of resistors R1 and R2, the reset circuit U1, and a diode of the common cathode diode D3, and then passes through the RC delay circuit composed of resistor R9 and capacitors C2, C3, and C4, and is sent to the input pin IN of the MOS driver chip U2.

[0034] In this embodiment, the control terminal ACC is sent to the IN pin of the MOS driver chip U2 through the fuse F1, the voltage divider circuit composed of R3 and R4, the resistor R5, another diode of the common cathode diode D3, and the RC delay circuit composed of the resistor R9 and the capacitors C2, C3, and C4. When the key is switched to the ACC gear, the control terminal ACC is powered, and the IN inputs a high-level signal to activate the MOS driver chip U2 and output the drive signal OUT. ACC is the abbreviation of AdaptiveCruiseControl, which means adaptive cruise control power supply in Chinese. It is controlled by the car key and supplies power to some components such as car audio.

[0035] In this embodiment, since an RC delay circuit is added to the control end of the MOS driver chip U2, the MOS driver chip U2 can continue to be turned on and maintain the original output when the voltage drops for a short time. Its function is to prevent the voltage drop at the moment of starting the car from causing the reset chip to output a low level. The RC delay allows the MOS driver chip U2 to continue to output. In specific applications, the required total capacitance will be calculated based on the required delay time, and the specifications and quantity of the capacitor will be selected.

[0036] In this embodiment, a transient voltage suppressor ZD1 (including two units ZD1A and ZD1B) is further provided to perform overvoltage protection on the output of the MOS driver chip U2.

[0037] The domain control automatic circuit-breaking circuit of this embodiment adopts a pure hardware design without an MCU, is not restricted by program control, and will not cause invalid shutdown due to a crash.

[0038] The beneficial effects of this domain control automatic circuit breaker circuit are:

[0039] The domain-controlled automatic circuit-breaking circuit of the present invention can be applied to automobiles and industrial products;

[0040] This design is a pure hardware design, and the stability of the product is more reliable than the combination of software and hardware;

[0041] The reset chip is a low-power product with a power consumption of only microamperes. When the control terminal voltage is lower than the set voltage, the MOS driver chip output is turned off, which will not increase the standby power consumption.

[0042] The circuit is simple and the overall design is smaller.

[0043] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes may be made to the present invention in form and details without departing from the spirit and scope of the present invention as defined by the appended claims, all of which are within the scope of protection of the present invention.

Claims

1. A domain-controlled automatic circuit breaker circuit, characterized in that: It includes a power input terminal, a drive output terminal and a ground terminal, as well as an undervoltage detection circuit and a MOS driver chip; The undervoltage detection circuit includes a first resistor voltage divider circuit and a reset circuit; The power input terminal is connected to the MOS driver chip to supply power to the MOS driver chip; and is connected to the input terminal of the reset circuit through a first resistor voltage divider circuit; The reset circuit has a hysteresis characteristic, and outputs a low level signal when it detects that the input voltage is lower than the lower hysteresis threshold, and outputs a high level signal when it detects that the input voltage is higher than the upper hysteresis threshold; The output end of the reset circuit is connected to the input end of the MOS driver chip to start and shut down the output of the MOS driver chip.

2. The domain-controlled automatic circuit-breaking circuit according to claim 1, characterized in that: The reset circuit is implemented by a reset chip with a low-side output.

3. The domain-controlled automatic circuit-breaking circuit according to claim 2, characterized in that: The domain-controlled automatic disconnection circuit also includes an RC delay circuit, which is connected in series between the output end of the reset circuit and the input end of the MOS driver chip.

4. The domain-controlled automatic circuit breaker circuit according to claim 3, characterized in that: The RC delay circuit includes a plurality of parallel-connected chip capacitors.

5. The domain-controlled automatic circuit-breaking circuit according to claim 3, characterized in that: The domain-controlled automatic circuit breaker circuit also includes an enabling circuit, a first diode, and a second diode; the output end of the reset circuit is connected to the anode of the first diode, and the cathode of the first diode is connected to the input end of the RC delay circuit; the enabling circuit includes a control end and a second resistor voltage divider circuit, the control end is connected to the input end of the second resistor voltage divider circuit, the output end of the second resistor voltage divider circuit is connected to the anode of the second diode, and the cathode of the second diode is connected to the input end of the RC delay circuit.

6. The domain-controlled automatic circuit-breaking circuit according to claim 5, characterized in that: The first diode and the second diode are two diode units of a common cathode diode.

7. The domain-controlled automatic circuit breaker circuit according to claim 5, characterized in that: A first fuse is also included between the control terminal and the second resistor voltage divider circuit.

8. The domain-controlled automatic circuit breaker according to claim 1, characterized in that: The MOS driver chip is a high-side driver MOS chip.

9. The domain-controlled automatic circuit-breaking circuit according to claim 1, characterized in that: The output end of the MOS driver chip is grounded through a transient voltage suppression device.

10. The domain-controlled automatic circuit-breaking circuit according to claim 1, characterized in that: A second fuse is also included between the power input terminal and the MOS driver chip.

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