Full-bridge circuit module and circuit system with over-temperature protection mechanism

Patent metadata

Field	Value
Publication number	US-12308773-B2
Application number	US-202318328446-A
Country	US
Kind code	B2
Filing date	Jun 2, 2023
Priority date	Jan 30, 2023
Publication date	May 20, 2025
Grant date	May 20, 2025

Abstract

A full-bridge circuit module with an over-temperature protection mechanism for driving an inductive load includes a full-bridge circuit and a comparator module. When the over-temperature protection mechanism is triggered, four switching transistors of the full-bridge circuit are turned off, and two body diodes of corresponding twos of the four switching transistors which are electrically connected to each other via the inductive load are conductive to form a load current flowing through the inductive load. When the load current causes a first output voltage of a first output terminal of the full bridge circuit to drop to a first comparison voltage and causes a second output voltage of a second output terminal of the full bridge circuit to reach a second comparison voltage, the comparator module controls the corresponding twos of the four switching transistors which are electrically connected to each other via the inductive load to be turned on.

First claim

What is claimed is:

1. A full-bridge circuit module with an over-temperature protection mechanism for driving an inductive load, comprising:
a full-bridge circuit comprising four switching transistors, and having a first output terminal and a second output terminal, wherein said inductive load is electrically connected between said first output terminal and said second output terminal;
a comparator module electrically connected to said full-bridge circuit; and
wherein when said over-temperature protection mechanism of said full-bridge circuit module is triggered, said four switching transistors of said full-bridge circuit are turned off, and two body diodes of corresponding twos of said four switching transistors which are electrically connected to each other via said inductive load form a path to generate a load current flowing through said inductive load; wherein when a first output voltage of said first output terminal is lower than a first comparison voltage and a second output voltage of said second output terminal is higher than a second comparison voltage, said comparator module controls said corresponding twos of said four switching transistors to be turned on.

2. The full-bridge circuit module of claim 1 , wherein when said over-temperature protection mechanism of said full-bridge circuit module is triggered, said four switching transistors of said full-bridge circuit module are turned off, and two body diodes of corresponding other twos of said four switching transistors which are electrically connected to each other via said inductive load are conductive to form a load current flowing through said inductive load; wherein when said second output voltage drops to a third comparison voltage and said first output voltage rises to a fourth comparison voltage, said comparator module controls said corresponding other twos of said four switching transistors to be turned on.

3. The full-bridge circuit module of claim 2 , wherein said four switching transistors comprise a first switching transistor, a second switching transistor, a third switching transistor, and a fourth switching transistor, wherein a first terminal of said first switching transistor is electrically connected to a first input terminal of said full-bridge circuit, a first terminal of said third switching transistor is electrically connected to a second input terminal of said full-bridge circuit, a second terminal of said first switching transistor and a first terminal of said second switching transistor are electrically connected to said first output terminal, a second terminal of said third switching transistor and a first terminal of said fourth switching transistor are electrically connected to said second output terminal, a second terminal of said second switching transistor and a second terminal of said fourth switching transistor are electrically connected to a low voltage, and said first input terminal receives a first input voltages, and said second input terminal receives a second input voltages.

4. The full-bridge circuit module of claim 3 , wherein said comparator module comprises a first comparator, a second comparator, a third comparator, and a fourth comparator, wherein a negative input terminal of said first comparator is electrically connected to said fourth comparison voltage, a positive input terminal of said first comparator is electrically connected to said first output terminal, and an output terminal of said first comparator is electrically connected to a control terminal of said first switching transistor, a negative input terminal of said second comparator is electrically connected to said first output terminal, a positive input terminal of said second comparator is electrically connected to said first comparison voltage, and an output terminal of said second comparator is electrically connected to a control terminal of said second switching transistor, a negative input terminal of said third comparator is electrically connected to said second comparison voltage, a positive input terminal of said third comparator is electrically connected to said second output terminal, an output terminal of said third comparator is electrically connected to a control terminal of said third switching transistor, a negative input terminal of said fourth comparator is electrically connected to said second output terminal, a positive input terminal of said fourth comparator is electrically connected to said third comparison voltage, and an output terminal of said fourth comparator is electrically connected to a control terminal of said fourth switching transistor.

5. The full-bridge circuit module of claim 4 , wherein said first comparison voltage is a negative value of a conduction threshold voltage of said body diode corresponding to said second switching transistor, said second comparison voltage is a sum of a conduction threshold voltage of said body diode corresponding to said third switching transistor and said second input voltage, said third comparison voltage is a negative value of a conduction threshold voltage of said body diode corresponding to said fourth switching transistor, and said fourth comparison voltage is a sum of a conduction threshold voltage of said body diode corresponding to said first switching transistor and said first input voltage.

6. The full-bridge circuit module of claim 4 , wherein each of said first comparator, said second comparator, said third comparator, and said fourth comparator is a hysteresis comparator.

7. The full-bridge circuit module of claim 3 , wherein in a condition that said four switching transistors are all turned off and two body diodes corresponding to said second switching transistor and said third switching transistor are conductive, when a first output voltage of said first output terminal drops to said first comparison voltage and a second output voltage of said second output terminal rises to said second comparison voltage, said comparator module controls said second switching transistor and said third switching transistor to be turned on; wherein in a condition that said four switching transistors are all turned off and two body diodes corresponding to said first switching transistor and said fourth switching transistor are conductive, when said second output voltage drops to a third comparison voltage and said first output voltage rises to a fourth comparison voltage, said comparator module controls said first switching transistor and said fourth switching transistor to be turned on.

8. The full-bridge circuit module of claim 1 , wherein said comparator module and said full-bridge circuit are integrated into a single chip.

9. A circuit system, comprising:
a full-bridge circuit module, comprising
a full-bridge circuit comprising four switching transistors, and having a first output terminal and a second output terminal, wherein said inductive load is electrically connected between said first output terminal and said second output terminal;
a comparator module electrically connected to said full-bridge circuit; and
wherein when said over-temperature protection mechanism of said full-bridge circuit module is triggered, said four switching transistors of said full-bridge circuit are turned off, and two body diodes of corresponding twos of said four switching transistors which are electrically connected to each other via said inductive load form a path to generate a load current flowing through said inductive load, wherein when a first output voltage of said first output terminal is lower than a first comparison voltage and a second output voltage of said second output terminal is higher than a second comparison voltage, said comparator module controls said corresponding twos of said four switching transistors which are electric

Assignees

• Nuvoton Technology Corp

Inventors

• Liu Chun Hsin

Classifications

• H03K17/082

  by feedback from the output to the control circuit · CPC title

• H03K2017/0806

  against excessive temperature · CPC title

• H02H5/04

  responsive to abnormal temperature {(specially adapted for electric machines H02H7/0852)} · CPC title

• H02P25/062 Primary

  of the induction type · CPC title

• H02H7/122 Primary

  for inverters, i.e. DC/AC converters · CPC title