Systems and methods for gate driver with field-adjustable UVLO

Patent metadata

Field	Value
Publication number	US-11056875-B2
Application number	US-201916245014-A
Country	US
Kind code	B2
Filing date	Jan 10, 2019
Priority date	Feb 23, 2018
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

Systems and methods for gate driver with field-adjustable undervoltage lockout (UVLO) are disclosed. A gate driver system comprises a control circuit and a driver circuit. The driver circuit incorporates a field-adjustable UVLO, a control logic, and an inverter. The level of the field-adjustable UVLO is adjustable by an external circuit, which can be a resistor based voltage divider. By setting the UVLO level externally adjustable and by moving a reference ground to the external voltage divider, the gate driver system is able to implement gate control for various load without needing extra ground pin.

First claim

What is claimed is:

1. A gate driver system comprising:
a control circuit outputs a control signal;
an external circuit comprising a reference ground, the external circuit outputs an external voltage; and
a driver circuit couples to the control circuit, the driver circuit comprising:
an adjustable undervoltage lockout (UVLO) coupled to the external circuit for providing the reference ground to the driver circuit, the adjustable UVLO receives the external voltage and a supply voltage to generate an UVLO output signal indicating a status of supply voltage, the adjustable UVLO has a trigger point adjustably determined by the external voltage;
a logic circuit receives the control signal and the adjustable UVLO output signal to generate a logic output signal;
an inverter receives the logic output signal to generate a driver output for gate control, in response to the adjustable UVLO being triggered, the logic circuit decouples communication between the control signal and the driver output.

2. The gate driver system of claim 1 wherein the external circuit is a voltage divider coupled to a voltage source to provide the external voltage, the supply voltage to the adjustable UVLO is provided by the voltage source.

3. The gate driver system of claim 2 wherein the voltage divider is a resistive voltage divider comprising at least one variable resistors such that the external voltage is adjustable.

4. The gate driver system of claim 3 wherein the supply voltage is a positive voltage with reference to the reference ground.

5. The gate driver system of claim 1 wherein the driver circuit couples to the control circuit with electrical isolation.

6. The gate driver system of claim 1 wherein the electrical isolation is implemented via capacitive coupling or optical isolation.

7. The gate driver system of claim 1 wherein the logic circuit is an AND gate.

8. The gate driver system of claim 1 wherein the inverter is driven by at least the supply voltage.

9. A gate driver circuit comprising:
a voltage divider coupled to a supply voltage to provide an external voltage with reference to a reference ground;
an adjustable undervoltage lockout (UVLO) coupled to the voltage divider for providing the reference ground to a driver circuit, the adjustable UVLO receives the supply voltage and the external voltage, the adjustable UVLO generates an UVLO output signal indicating a status of the supply voltage, the adjustable UVLO has a trigger point adjustably determined by the external voltage;
a logic circuit receiving a control signal and the UVLO output signal to generate a logic output signal; and
an inverter receiving the logic output signal to generate a driver output for gate control, in response to the adjustable UVLO being triggered, the logic circuit disables communication between the control signal and the driver output.

10. The gate driver of claim 9 wherein the logic circuit is an AND gate.

11. The gate driver of claim 9 wherein the inverter is driven by at least the supply voltage.

12. The gate driver of claim 9 wherein the voltage divider is a resistive voltage divider comprising at least one variable resistor such that the external voltage is adjustable.

13. A method for gate driving, the method comprising:
receiving, at an adjustable undervoltage lockout (UVLO), an external voltage and a supply voltage referenced to a reference ground external to the adjustable UVLO;
generating, by the adjustable UVLO, an UVLO output signal indicating a status of the supply voltage, the external voltage is adjustable to determine a trigger point of the adjustable UVLO;
receiving, at a logic circuit, a control signal and the UVLO output signal to generate a logic output signal; and
receiving, at an inverter, the logic output signal to generate a driver output for gate control, in response to the adjustable UVLO being triggered, the logic circuit decouples communication between the control signal and the driver output.

14. The method of claim 13 wherein the logic circuit receives the control circuit with electrical isolation.

15. The method of claim 14 wherein the electrical isolation is a capacitive coupling or an optical isolation.

16. The method of claim 13 wherein the external circuit is a voltage divider coupled to a voltage source to provide the external voltage, the supply voltage to adjustable UVLO is provided by the voltage source.

17. The method of claim 16 wherein the voltage divider is a resistive voltage divider comprising at least one variable resistors such that the external voltage is adjustable.

18. The method of claim 13 wherein the supply voltage is a positive voltage with reference to the reference ground.

19. The method of claim 13 wherein the logic circuit is an AND gate.

20. The method of claim 13 wherein the inverter is driven by at least the supply voltage.

Assignees

• Maxim Integrated Products

Inventors

• Hematy Arman

Classifications

• H02J7/44

  between battery management systems and power sources · CPC title

• H03K17/689 Primary

  with galvanic isolation between the control circuit and the output circuit (H03K17/78 takes precedence) · CPC title

• H02H3/243 Primary

  for DC systems · CPC title

• H03K19/08

  using semiconductor devices (H03K19/173 takes precedence; wherein the semiconductor devices are only diode rectifiers H03K19/12) · CPC title

• H03K17/567 Primary

  Circuits characterised by the use of more than one type of semiconductor device, e.g. BIMOS, composite devices such as IGBT · CPC title