US 11,128,130 B2Granted

Protection circuit with bidirectional surge protection

AssigneeShanghai Awinic Technology Co., LTD

InventorsXucheng Luo, Jiantao Cheng, Jianwei Hu, Chuankui Wu, Yongqiang He, Yan Jiang

Life of this patent

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Abstract

A protection circuit is provided. A control circuit receives an input voltage. In a case that the input voltage is lower than a negative threshold voltage, the control circuit outputs a first control voltage to a surge bleeder circuit through a first output end of the control circuit, to control the surge bleeder circuit to discharge the input voltage and output a first bleeder current. In a case that the input voltage is higher than a positive threshold voltage, the control circuit outputs a second control voltage to the surge bleeder circuit through a second output end of the control circuit, to control the surge bleeder circuit to discharge the input voltage and output a second bleeder current.

Claims8

Dependent claims

A protection circuit for power supply, comprising:

a first gate drive circuit;
a second gate drive circuit;
a transistor M2;
a diode D2;
a control circuit;
and
a surge bleeder circuit, wherein
a first end of the first gate drive circuit is connected to a power supply input end, and a second end of the first gate drive circuit is connected to the surge bleeder circuit;
a first terminal of the transistor M2 is connected to a power supply output end, a control terminal of the transistor M2 is connected to the second gate drive circuit, and a second terminal of the transistor M2 is connected to the surge bleeder circuit;
an anode of the diode D2 is connected to the first terminal of the transistor M2, and a cathode of the diode D2 is connected to the second terminal of the transistor M2;
a first end of the second gate drive circuit is connected to the power supply output end, and a second end of the second gate drive circuit is connected to the control terminal of the transistor M2;
and
the control circuit is configured to:
receive an input voltage;
output a first control voltage to the surge bleeder circuit through a first output end of the control circuit, to control the surge bleeder circuit to perform discharging based on the first control voltage and output a first bleeder current, in a case that the input voltage is lower than a preset negative threshold voltage;
and output a second control voltage to the surge bleeder circuit through a second output end of the control circuit, to control the surge bleeder circuit to perform discharging based on the second control voltage and output a second bleeder current, in a case that the input voltage is higher than a preset positive threshold voltage;
wherein the control circuit comprises:
a resistor R1;
a resistor R2;
a transistor M4;
a diode D4;
a diode Z1;
a diode Z3;
a zener diode Z2;
and
a zener diode Z4, and wherein:
a cathode of the diode Z1 is connected to a cathode of the zener diode Z2, and an anode of the diode Z1 is connected to the power supply input end;
an anode of the zener diode Z2 serves as the second output end of the control circuit and is grounded through the resistor R1;
a first terminal of the transistor M4 is connected to the power supply input end, a second terminal of the transistor M4 is connected to the first output end of the control circuit through the resistor R2;
an anode of the diode D4 is connected to the first terminal of the transistor M4, and a cathode of the diode D4 is connected to the second terminal of the transistor M4;
a cathode of the diode Z3 is connected to a cathode of the zener diode Z4, and an anode of the diode Z3 is grounded;
and
an anode of the zener diode Z4 is connected to the first output end of the control circuit.

30 more elements

A protection circuit for power supply, comprising:

a control circuit, comprising an input end and at least one output end, wherein the at least output end comprises a first output end and a second output end;
and
a surge bleeder circuit, connected to the control circuit and coupled between a power supply and a ground;
and
a switch coupled to the surge bleeder circuit and an output end of the protection circuit,
wherein the control circuit comprises:
a resistor R1;
a resistor R2;
a transistor M4;
a diode D4;
a diode Z1;
a diode Z3;
a zener diode Z2;
and
a zener diode Z4, and wherein:
a cathode of the diode Z1 is connected to a cathode of the zener diode Z2, and an anode of the diode Z1 is connected to the power supply input end;
an anode of the zener diode Z2 serves as the second output end of the control circuit and is grounded through the resistor R1;
a first terminal of the transistor M4 is connected to the power supply input end, a second terminal of the transistor M4 is connected to the first output end of the control circuit through the resistor R2;
an anode of the diode D4 is connected to the first terminal of the transistor M4, and a cathode of the diode D4 is connected to the second terminal of the transistor M4;
a cathode of the diode Z3 is connected to a cathode of the zener diode Z4, and an anode of the diode Z3 is grounded;
and
an anode of the zener diode Z4 is connected to the first output end of the control circuit;
and
wherein the control circuit is configured to:
receive an input voltage;
output a first control voltage to the surge bleeder circuit through a first output end of the control circuit, to control the surge bleeder circuit to perform discharging based on the first control voltage and output a first bleeder current, in a case that the input voltage is lower than a preset negative threshold voltage;
and output a second control voltage to the surge bleeder circuit through a second output end of the control circuit, to control the surge bleeder circuit to perform discharging based on the second control voltage and output a second bleeder current, in a case that the input voltage is higher than a preset positive threshold voltage.

24 more elements

Dependencies are inferred from the claim text.

Facts

Application: 16/692,942Filed 22 Nov 2019
Priority: CN 201811605090.126 Dec 2018
Published: US 2020/0212672 A12 Jul 2020
Granted: 21 Sep 2021
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

H02H 9/045
Responsive to excess voltage: adapted to a particular application and not provided for elsewhere
H02H 9/041
Responsive to excess voltage: using a short-circuiting device
H02H 11/003
In case of inverted polarity or connection; with switching for obtaining correct connection: using a field effect transistor as protecting element…
H02H 3/22
Responsive to excess voltage: of short duration, e.g. lightning