IRREGULARITY DETECTION DEVICE FOR A POWER SWITCH

• US 20160126720A1
• Filed: 10/31/2014
• Published: 05/05/2016
• Est. Priority Date: 10/31/2014
• Status: Active Grant

• Current Assignee: Acbel Polytech Incorporated
• Original Assignee: Acbel Polytech Incorporated
• Inventors: Yeh, Chia-An
• Granted Patent: US 9,448,607 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/28 Supervision thereof, e.g. detecting power-supply failure by out of limits supervision
• CPC Class Codes: H02H 3/20 responsive to excess voltage
• CPC Class Codes: H02H 7/1213 for DC-DC converters
• CPC Class Codes: H02M 1/0058 by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 1/327 against abnormal temperatures
• CPC Class Codes: H02M 1/42 Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
• CPC Class Codes: H02M 1/4225 using a non-isolated boost converter
• CPC Class Codes: H02M 3/335 using semiconductor devices only
• CPC Class Codes: H02M 3/33546 with automatic control of the output voltage or current H02M3/33561 takes precedence
• CPC Class Codes: H03K 17/145 in field-effect transistor switches
• CPC Class Codes: H03K 2217/0027 Measuring means of, e.g. currents through or voltages across the switch
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y02P 80/10 Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier

Abstract

An irregularity detection device for a power switch determines if a temperature-dependent resistance on a current path of the power switch is abnormal according to if a voltage on the current path is greater than or equal to a configuration value when the power switch is turned on, and generates an irregularity alarm associated with the power switch based on the determination result.

Claims

1. An irregularity detection device for a power switch, wherein the irregularity detection device is connected to a current path of a power switch and comprises:

a voltage-dividing circuit having a voltage-dividing node; and

a voltage-controlled switch connected between the voltage-dividing node of the voltage-dividing circuit and the current path of the power switch;

wherein

when a voltage on the current path of the power switch is less than a first configuration value, the voltage-controlled switch is turned on for a voltage at the voltage-dividing node to be less than a second configuration value; and

when the voltage on the current path of the power switch is greater than or equal to the first configuration value, the voltage-controlled switch is turned off for the irregularity detection device to generate an irregularity alarm when the voltage at the voltage-dividing node is greater than or equal to the second configuration value.

2. The irregularity detection device as claimed in claim 1, wherein the voltage-controlled switch is a diode.

3. The irregularity detection device as claimed in claim 2, wherein an anode of the voltage-controlled switch is connected to the voltage-dividing node of the voltage-dividing circuit, and a cathode of the voltage-controlled switch is connected to the current path of the power switch.

4. The irregularity detection device as claimed in claim 3, wherein the power switch has a drain, a source and a gate, and the voltage-dividing circuit has a first resistor and a second resistor, wherein the first resistor and the second resistor are connected in series with each other, the voltage-dividing node is located at a common end of the first resistor and the second resistor, the other end of the first resistor is connected to a DC (Direct Current) voltage source, and the other end of the second resistor is connected to the source of the power switch and to the ground.

5. The irregularity detection device as claimed in claim 4, wherein the second configuration value is determined by a voltage-dividing equation with values of the DC voltage source, the first resistor and the second resistor in the voltage-dividing circuit as variables in the voltage-dividing equation.

6. The irregularity detection device as claimed in claim 5, wherein the first configuration value is a forward-biased voltage of the voltage-controlled switch.

7. The irregularity detection device as claimed in claim 1, wherein the power switch is a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), and the current path is formed between a drain and a source of the power switch.

8. The irregularity detection device as claimed in claim 1, wherein the voltage-dividing node of the voltage-dividing circuit is connected to a digital controller.

9. The irregularity detection device as claimed in claim 6, wherein the voltage-dividing node of the voltage-dividing circuit is connected to a digital controller.

10. The irregularity detection device as claimed in claim 7, wherein the voltage-dividing node of the voltage-dividing circuit is connected to a digital controller.

11. The irregularity detection device as claimed in claim 8, wherein the digital controller drives the power switch with a driving signal to periodically turn on the power switch and to sample the voltage at the voltage-dividing node during each duty cycle of the power switch.

12. The irregularity detection device as claimed in claim 9, wherein the digital controller drives the power switch with a driving signal to periodically turn on the power switch and to sample the voltage at the voltage-dividing node during each duty cycle of the power switch.

13. The irregularity detection device as claimed in claim 10, wherein the digital controller drives the power switch with a driving signal to periodically turn on the power switch and to sample the voltage at the voltage-dividing node during each duty cycle of the power switch.

14. The irregularity detection device as claimed in claim 8, wherein the digital controller is a power factor correction (PFC) controller.

15. The irregularity detection device as claimed in claim 9, wherein the digital controller is a power factor correction (PFC) controller.

16. The irregularity detection device as claimed in claim 10, wherein the digital controller is a power factor correction (PFC) controller.

17. The irregularity detection device as claimed in claim 8, wherein the digital controller is a pulse width modulation (PWM) controller.

18. The irregularity detection device as claimed in claim 9, wherein the digital controller is a pulse width modulation (PWM) controller.

19. The irregularity detection device as claimed in claim 10, wherein the digital controller is a pulse width modulation (PWM) controller.