CN-224231945-U - Direct current power-down detection circuit

Abstract

The utility model discloses a direct current power failure detection circuit which comprises a comparator U3, a first voltage division unit, a second voltage division unit, a control chip MCU, a voltage stabilizing component and an energy storage unit, wherein the input end of the voltage stabilizing component is connected with an external direct current power supply, the output end of the voltage stabilizing component is respectively connected with the energy storage unit and the VDD end of the control chip MCU, the normal phase input end of the comparator U3 is connected with the first voltage division unit, one end of the first voltage division unit is respectively connected with the external direct current power supply and the input end of the voltage stabilizing component, the other end of the first voltage division unit is grounded, the reverse input end of the comparator U3 is connected with the second voltage division unit, one end of the second voltage division unit is connected with the output end of the voltage stabilizing component, the other end of the second voltage division unit is grounded, the positive power supply end of the comparator U3 is connected with the output end of the voltage stabilizing component, the negative power supply end of the comparator U3 is grounded, the output end of the comparator U3 is connected with the IO pin of the control chip MCU, and the VDD pin of the control chip MCU is respectively connected with the energy storage unit and the output end of the voltage stabilizing component.

Inventors

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Assignees

• 广东奥科伟业科技发展有限公司

Dates

Publication Date

20260512

Application Date

20250523

Claims (9)

1. 1. A direct current power failure detection circuit is characterized by comprising a comparator U3, a first voltage division unit (1), a second voltage division unit (2), a control chip MCU, a voltage stabilizing component (3) and an energy storage unit (4), wherein the input end of the voltage stabilizing component (3) is connected with an external direct current power supply, the output end of the voltage stabilizing component (3) is respectively connected with the energy storage unit (4) and the VDD end of the control chip MCU, the positive input end of the comparator U3 is connected with the first voltage division unit (1), one end of the first voltage division unit (1) is respectively connected with the external direct current power supply and the input end of the voltage stabilizing component (3), the other end of the first voltage division unit is grounded, the reverse input end of the comparator U3 is connected with the second voltage division unit (2) and the output end of the voltage stabilizing component (3) is connected, the other end of the second voltage division unit (2) is grounded, the positive power supply end of the comparator U3 is connected with the output end of the voltage stabilizing component (3), and the other end of the comparator U3 is grounded, and the output end of the voltage stabilizing component (4) is connected with the output end of the voltage stabilizing component (4) of the chip.
2. 2. The direct current power failure detection circuit according to claim 1, wherein the voltage stabilizing component (3) comprises a first filtering unit (31), a voltage stabilizing chip U2 and a second filtering unit (32), one end of the first filtering unit (31) is respectively connected with an external direct current power supply and an input end of the voltage stabilizing chip U2, the other end of the first filtering unit is connected with the input end of the voltage stabilizing chip U2, an output end of the voltage stabilizing chip U2 is connected with the second filtering unit (32), the other end of the second filtering unit (32) is respectively connected with the energy storage unit (4) and a VDD pin of the control chip MCU, and the other end of the second filtering unit (32) is also connected with the second voltage dividing unit (2) and a positive power supply end of the comparator U3.
3. 3. The direct current power failure detection circuit according to claim 1, wherein the energy storage unit (4) comprises a capacitor C7, one end of the capacitor C7 is respectively connected to the VDD pin of the control chip MCU and the output end of the voltage stabilizing component (3), and the other end is grounded.
4. 4. The direct current power failure detection circuit according to claim 1, further comprising a third filtering unit (5), wherein one end of the third filtering unit (5) is respectively connected with the VDD pin of the control chip MCU, the energy storage unit (4) and the output end of the voltage stabilizing component (3), and the other end of the third filtering unit is grounded.
5. 5. The direct current power failure detection circuit according to claim 1, further comprising a diode D1, wherein an anode of the diode D1 is connected to an external direct current power supply, and a cathode thereof is connected to an input terminal of the voltage stabilizing component (3).
6. 6. The direct current power failure detection circuit according to claim 2, further comprising a diode D3, wherein an anode of the diode D3 is connected to the second filtering unit (32), and a cathode of the diode D3 is connected to the energy storage unit (4) and a VDD pin of the control chip MCU, respectively.
7. 7. The direct current power failure detection circuit according to claim 1, wherein the first voltage division unit (1) comprises a resistor R1 and a resistor R5, one end of the resistor R1 is connected with an external direct current power supply and an input end of the voltage stabilizing component (3), the other end of the resistor R1 is respectively connected with the resistor R5 and a positive input end of the comparator U3, the other end of the resistor R5 is grounded, the second voltage division unit (2) comprises a resistor R2 and a resistor R6, one end of the resistor R2 is connected with an output end of the voltage stabilizing component (3), the other end of the resistor R2 is respectively connected with the resistor R6 and an inverting input end of the comparator U3, and the other end of the resistor R6 is grounded.
8. 8. The direct current power failure detection circuit according to claim 1, further comprising a resistor R4, wherein one end of the resistor R4 is connected to the output end of the comparator U3, and the other end of the resistor R4 is connected to the IO pin of the control chip MCU.
9. 9. The direct current power failure detection circuit according to claim 1, further comprising a resistor R3, wherein one end of the resistor R3 is connected to a power supply end of the comparator U3 and an output end of the voltage stabilizing component (3), and the other end of the resistor R3 is connected to an output end of the comparator U3 and an IO pin of the control chip MCU.

Description

Direct current power-down detection circuit Technical Field The utility model relates to the technical field of power-down detection circuits, in particular to a direct-current power-down detection circuit. Background In the use process of the electronic equipment, when the power supply fails or the power supply is exhausted, the voltage of the power supply suddenly drops to a very low level, so that power failure is caused, the electronic equipment cannot work normally, and data in the power failure cannot be stored in time. Therefore, when the electronic equipment is powered off, it is important to take corresponding measures in time to ensure the safety of data and the reliability of the equipment. Disclosure of utility model Aiming at the defects of the prior art, a direct current power failure detection circuit is provided. The utility model provides a direct current power failure detection circuit which comprises a comparator U3, a first voltage division unit, a second voltage division unit, a control chip MCU, a voltage stabilizing component and an energy storage unit, wherein the input end of the voltage stabilizing component is connected with an external direct current power supply, the output end of the voltage stabilizing component is respectively connected with the energy storage unit and the VDD end of the control chip MCU, the positive input end of the comparator U3 is connected with the first voltage division unit, one end of the first voltage division unit is respectively connected with the external direct current power supply and the input end of the voltage stabilizing component, the other end of the first voltage division unit is grounded, the reverse input end of the comparator U3 is connected with the second voltage division unit, one end of the second voltage division unit is connected with the output end of the voltage stabilizing component, the other end of the second voltage division unit is grounded, the positive power end of the comparator U3 is connected with the output end of the voltage stabilizing component, the negative power supply of the comparator U3 is grounded, the output end of the comparator U3 is connected with the IO pin of the control chip MCU, the VDD pin of the control chip MCU is respectively connected with the energy storage unit and the output end of the voltage stabilizing component, and the other end of the energy storage unit is grounded. According to one embodiment of the utility model, the voltage stabilizing component comprises a first filtering unit, a voltage stabilizing chip U2 and a second filtering unit, wherein one end of the first filtering unit is respectively connected with an external direct current power supply and the input end of the voltage stabilizing chip U2, the other end of the first filtering unit is connected with the input end of the voltage stabilizing chip U2, the output end of the voltage stabilizing chip U2 is connected with the second filtering unit, the other end of the second filtering unit is respectively connected with the energy storage unit and the VDD pin of the control chip MCU, and the other end of the second filtering unit is also connected with the positive power supply end of the second voltage dividing unit and the comparator U3. According to an embodiment of the present utility model, the energy storage unit includes a capacitor C7, one end of the capacitor C7 is connected to the VDD pin of the control chip MCU and the output end of the voltage stabilizing component, respectively, and the other end is grounded. According to an embodiment of the present utility model, the power supply further includes a third filtering unit, one end of the third filtering unit is connected to the VDD pin of the control chip MCU, the energy storage unit, and the output end of the voltage stabilizing component, respectively, and the other end of the third filtering unit is grounded. According to an embodiment of the present utility model, the voltage stabilizing device further comprises a diode D1, wherein an anode of the diode D1 is connected to an external dc power supply, and a cathode of the diode D1 is connected to an input terminal of the voltage stabilizing device. According to an embodiment of the present utility model, the power supply further includes a diode D3, wherein an anode of the diode D3 is connected to the second filtering unit, and a cathode of the diode D3 is connected to the energy storage unit and the VDD pin of the control chip MCU, respectively. According to one embodiment of the utility model, the first voltage dividing unit comprises a resistor R1 and a resistor R5, one end of the resistor R1 is connected with an external direct current power supply and the input end of the voltage stabilizing component, the other end of the resistor R1 is respectively connected with the resistor R5 and the positive input end of the comparator U3, the other end of the resistor R5 is grounded, the second voltage dividing unit