DAMPER CIRCUIT FOR SWITCHED DIMMING

• US 20130057167A1
• Filed: 07/29/2011
• Published: 03/07/2013
• Est. Priority Date: 07/29/2011
• Status: Active Grant

• Current Assignee: Power Integrations Incorporated
• Original Assignee: Power Integrations Incorporated
• Inventors: Angeles, Christian Pura
• Granted Patent: US 8,928,235 B2
• Time in Patent Office: Days
• US Class Current: 315/200.R
• CPC Class Codes: H05B 45/31 Phase-control circuits
• CPC Class Codes: H05B 45/355 Power factor correction [PFC]; Reactive power compensation
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• CPC Class Codes: H05B 45/395 Linear regulators
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

A power converter includes dimmer circuit, a rectifier circuit, and a thyristor damper circuit. The dimmer circuit provides a dimmer voltage in response to an input voltage. The rectifier circuit provides a rectified voltage in response to the dimmer voltage. The thyristor damper circuit dampens an input current associated with the rectified voltage based on the input current and ceases dampening the rectified voltage based on the rectified voltage.

Claims

1. A power converter comprising:

a dimmer circuit that is operative to provide a dimmer voltage in response to an input voltage;

a rectifier circuit that is operative to provide a rectified voltage in response to the dimmer voltage; and

a thyristor damper circuit that is operative to dampen an input current associated with the rectified voltage based on the input current and to cease dampening the rectified voltage based on the rectified voltage.

2. The power converter of claim 1 wherein the thyristor damper circuit is operative to dampen the input current when the input current reaches a current threshold and to cease to dampening the input current when the rectified voltage reaches a voltage threshold.

3. The power converter of claim 1 wherein the thyristor damper circuit comprises:

a damper circuit;

a bypass enable circuit, operatively coupled to the damper circuit, that is operative to provide a bypass enable voltage based on the rectified voltage;

a damper bypass circuit, operatively coupled to the damper circuit, that is operative to bypass the damper circuit in response to the bypass enable voltage.

4. The power converter of claim 3 wherein the damper bypass circuit bypasses the damper circuit when the bypass enable voltage reaches a voltage threshold.

5. The power converter of claim 4 wherein the bypass enable voltage reaches the voltage threshold after a predetermined time.

6. The power converter of claim 1 wherein the dimmer circuit comprises a triode for alternating current circuit.

7. The power convertor of claim 1 wherein the thyristor damper circuit comprises a silicon controlled rectifier circuit.

8. The power converter of claim 3 wherein:

the damper circuit comprises a first resistance circuit having a first end and a second end, wherein the first end is operatively coupled to the rectifier circuit;

the bypass enable circuit comprises;

a second resistance circuit having a third end and a fourth end, wherein the third end is operatively coupled to the rectifier circuit; and

a capacitance circuit having a fifth end and a sixth end, wherein the fifth end is operatively coupled to the fourth end and the sixth end is operatively coupled to the first end; and

the damper bypass circuit comprises;

a thyristor circuit having a seventh end, an eighth end, and a ninth end, wherein the seventh end is operatively coupled to the first end, the eighth end is operatively coupled to the second end, and the ninth end is operatively coupled to the fifth end.

9. The power converter of claim 3 wherein:

the damper circuit comprises a first resistance circuit having a first end and a second end, wherein the first end is operatively coupled to the rectifier circuit;

the bypass enable circuit comprises;

a second resistance circuit having a third end and a fourth end, wherein the third end is operatively coupled to the rectifier circuit; and

a capacitance circuit having a fifth end and a sixth end, wherein the fifth end is operatively coupled to the fourth end and the sixth end is operatively coupled to the second end; and

the damper bypass circuit comprises;

a thyristor circuit having a seventh end, an eighth end, and a ninth end, wherein the seventh end is operatively coupled to the first end, the eighth end is operatively coupled to the second end, and the ninth end is operatively coupled to the fifth end.

10. The power converter of claim 1 wherein the thyristor damper circuit is operative to dampen the input current for a predetermined time.

20. The power converter of claim 1 wherein the thyristor damper circuit is operative to dampen the input current for a predetermined time.

11. A method of damping current for a power converter having a triode alternating current switch dimmer circuit, comprising:

providing a dimmer voltage in response to an input voltage;

providing a rectified voltage in response to the dimmer voltage;

bypassing a damping circuit when the rectified voltage reaches a voltage threshold; and

ceasing bypassing the damping circuit when a input current associated with the rectified voltage reaches a current threshold.

12. The method of claim 11 wherein the input current is dampened when the input current reaches the current threshold and the input current ceases to be dampened when the rectified voltage reaches the voltage threshold.

13. A power converter comprising:

a switch;

an energy transfer element, wherein a current flows through the energy transfer element when the switch is in an on condition;

a controller that is operative to provide a drive signal based on a duty cycle, wherein the switch is operative to transition between the on condition and an off condition in response to the drive signal;

a dimmer circuit that is operative to provide a dimmer voltage in response to an input voltage;

a rectifier circuit that is operative to provide a rectified voltage in response to the dimmer voltage; and

a thyristor damper circuit, operatively coupled to the energy transfer element, that is operative to dampen a input current associated with the rectified voltage based on the input current and to cease dampening the rectified voltage based on the rectified voltage.

14. The power converter of claim 13 wherein the thyristor damper circuit is operative to dampen the input current when the input current reaches a current threshold and to cease to dampening the input current when the rectified voltage reaches a voltage threshold.

15. The power converter of claim 13 wherein the thyristor damper circuit comprises:

a damper circuit;

a bypass enable circuit, operatively coupled to the damper circuit, that is operative to provide a bypass enable voltage based on the rectified voltage;

a damper bypass circuit, operatively coupled to the damper circuit, that is operative to bypass the damper circuit in response to the bypass enable voltage.

16. The power converter of claim 15 wherein the damper bypass circuit bypasses the damper circuit when the bypass enable voltage reaches a voltage threshold.

17. The power converter of claim 16 wherein the bypass enable voltage reaches the voltage threshold after a predetermined time.

18. The power converter of claim 13 wherein the dimmer circuit comprises a triode for alternating current circuit.

19. The power converter of claim 13 wherein the thyristor damper circuit comprises a silicon controlled rectifier circuit.