Detection circuit and detection method

Abstract

This invention provides a detection circuit for a driving circuit. The detection circuit includes a comparison circuit and a logic circuit. The comparison circuit is coupled to an output pin of the driving circuit. The comparison circuit receives an output signal from the output pin, compares the output signal with a first reference signal level to generate a first comparison result, and compares the output signal with a second reference signal level to generate a second comparison result, wherein the first reference signal level is different from the second reference signal level. The logic circuit is coupled to the comparison circuit. The logic circuit generates a detection result based on the first comparison result and the second comparison result to indicate whether a short circuit has occurred between an output pin and an adjacent output pin in the driving circuit.

Claims

1. A detection circuit for use in a drive circuit, comprising: A comparator circuit, coupled to an output pin of the driver circuit, receives an output signal from the output pin of the driver circuit, compares the output signal with a first reference signal level to generate a first comparison result, and compares the output signal with a second reference signal level to generate a second comparison result, wherein the first reference signal level is different from the second reference signal level; and a logic circuit, coupled to the comparator circuit, generates a detection result based on the first comparison result and the second comparison result to indicate whether a short circuit has occurred between the output pin of the driver circuit and an adjacent output pin.

2. The detection circuit as claimed in claim 1, wherein the first reference signal level is greater than the second reference signal level, wherein when the first comparison result shows that a signal level of the output signal is less than the first reference signal level, and the second comparison result shows that the signal level of the output signal is greater than the second reference signal level, the logic circuit generates the detection result to indicate that a short circuit has occurred between the output pin and the adjacent output pin in the drive circuit.

3. The detection circuit as claimed in claim 1, wherein the first reference signal level is a first reference voltage and the second reference signal level is a second reference voltage, wherein the comparison circuit includes: A first comparator, coupled to the output pin of the driving circuit, is used to receive the output signal and compare a voltage of the output signal with the first reference voltage to generate the first comparison result; and a second comparator, coupled to the output pin of the driving circuit, is used to receive the output signal and compare the voltage of the output signal with the second reference voltage to generate the second comparison result, wherein the first reference voltage is different from the second reference voltage.

4. The detection circuit as claimed in claim 3, wherein the first reference voltage is greater than the second reference voltage, wherein when the first comparison result shows that the voltage of the output signal is less than the first reference voltage and the second comparison result shows that the voltage of the output signal is greater than the second reference voltage, the logic circuit generates the detection result to indicate that a short circuit has occurred between the output pin and the adjacent output pin in the drive circuit.

5. The detection circuit as claimed in claim 3, wherein the first reference voltage is less than a gate high voltage and the second reference voltage is greater than a gate low voltage.

6. The detection circuit as claimed in claim 1, wherein the first reference signal level is a first reference current, the second reference signal level is a second reference current, the first reference current is different from the second reference current, wherein the comparison circuit includes: A first voltage-to-current converter, coupled to the output pin of the drive circuit, is used to receive the output signal and convert a voltage of the output signal into a current of the output signal; a second voltage-to-current converter is used to receive a first reference voltage and convert the first reference voltage into the first reference current; a third voltage-to-current converter is used to receive a second reference voltage and convert the second reference voltage into the second reference current; and a current comparator, coupled to the first voltage-to-current converter, the second voltage-to-current converter, and the third voltage-to-current converter, is used to compare the current of the output signal with the first reference current to generate the first comparison result, and to compare the current of the output signal with the second reference current to generate the second comparison result.

7. The detection circuit as claimed in claim 6, wherein the first reference current is greater than the second reference current, wherein when the first comparison result shows that the current of the output signal is less than the first reference current and the second comparison result shows that the current of the output signal is greater than the second reference current, the logic circuit generates the detection result to indicate that a short circuit has occurred between the output pin and the adjacent output pin in the drive circuit.

8. The detection circuit as claimed in claim 1, wherein the logic circuit comprises: A mutual exclusion gate circuit, coupled to the comparator circuit, is used to generate the detection result based on the first comparison result and the second comparison result.

9. The detection circuit as claimed in claim 1, further comprising: A surge cancellation circuit, coupled to the logic circuit, is used to generate a surge-canceled detection result based on the detection result generated by the logic circuit. The surge cancellation circuit generates the surge-canceled detection result by removing the detection result determined based on a rising edge or a falling edge of the output signal from the detection result generated by the logic circuit.

10. The detection circuit as claimed in claim 1, further comprising: A counting circuit is used to determine whether a short circuit has occurred at the output pin within a predetermined number of consecutive frame periods based on the detection result or a detection result after surge suppression, and to generate an advanced detection result accordingly.

11. A detection method for a driving circuit, comprising: The driver circuit receives an output signal from an output pin; compares the output signal with a first reference signal level to generate a first comparison result; compares the output signal with a second reference signal level to generate a second comparison result, wherein the first reference signal level is different from the second reference signal level; and generates a detection result based on the first comparison result and the second comparison result to indicate whether a short circuit has occurred between the output pin and an adjacent output pin in the driver circuit.

12. The detection method as claimed in claim 11, wherein the first reference signal level is greater than the second reference signal level, wherein the detection method further comprises: When the first comparison result shows that a signal level of the output signal is less than the first reference signal level, and the second comparison result shows that the signal level of the output signal is greater than the second reference signal level, the detection result is generated to indicate that a short circuit has occurred between the output pin and the adjacent output pin in the drive circuit.

13. The detection method as claimed in claim 11, wherein the first reference signal level is a first reference voltage and the second reference signal level is a second reference voltage, wherein the detection method further comprises: The voltage of the output signal is compared with the first reference voltage to generate the first comparison result; And compare the voltage of the output signal with the second reference voltage to generate the second comparison result, wherein the first reference voltage is different from the second reference voltage.

14. The detection method as claimed in claim 13, wherein the first reference voltage is greater than the second reference voltage, wherein the detection method further comprises: When the first comparison result shows that the voltage of the output signal is less than the first reference voltage, and the second comparison result shows that the voltage of the output signal is greater than the second reference voltage, the detection result is generated to indicate that a short circuit has occurred between the output pin and the adjacent output pin in the drive circuit.

15. The detection method as claimed in claim 13, wherein the first reference voltage is less than a gate high voltage and the second reference voltage is greater than a gate low voltage.

16. The detection method as claimed in claim 11, wherein the first reference signal level is a first reference current, the second reference signal level is a second reference current, the first reference current being different from the second reference current, and the detection method further comprising: Convert the voltage of the output signal into the current of the output signal; Convert a first reference voltage into the first reference current; The second reference voltage is converted into the second reference current; and the current of the output signal is compared with the first reference current to generate the first comparison result, and the current of the output signal is compared with the second reference current to generate the second comparison result.

17. The detection method as claimed in claim 16, wherein the first reference current is greater than the second reference current, and wherein the detection method further comprises: When the first comparison result shows that the current of the output signal is less than the first reference current and the second comparison result shows that the current of the output signal is greater than the second reference current, the detection result is generated to indicate that a short circuit has occurred between the output pin and the adjacent output pin in the drive circuit.

18. The detection method as described in claim 11, further comprising: The detection result is generated by a mutual exclusion circuit based on the first comparison result and the second comparison result.

19. The detection method as described in claim 11, further comprising: The detection result is used to generate a surge-free detection result, which includes removing a detection result determined based on a rising edge or a falling edge of the output signal from the detection result generated based on the first comparison result and the second comparison result.

20. The detection method as described in claim 11, further comprising: Based on the detection result or the detection result after the surge has been eliminated, it is determined whether a short circuit has occurred in the output pin within a predetermined number of consecutive frame periods, and an advanced detection result is generated accordingly.

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