Switch current control to shape input current

Patent metadata

Field	Value
Publication number	US-9750102-B1
Application number	US-201615092445-A
Country	US
Kind code	B1
Filing date	Apr 6, 2016
Priority date	Apr 6, 2016
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

A controller for use in a power converter includes a first edge detection circuit that receives a first input sense signal representative of an input of the power converter coupled to a dimmer circuit, and generates a first edge detection signal in response to the first input sense signal. A shaping circuit receives the first edge detection signal from the first edge detection circuit. The shaping circuit generates a first shape signal in response to the first edge detection signal. A drive circuit receives the first shape signal and a feedback signal representative of an output of the power converter. The drive circuit generates the drive signal in response to the feedback signal to control switching of a power switch of the power converter. The drive circuit switches the power switch in a first higher current mode for a first duration in response to the first shape signal.

First claim

What is claimed is:

1. A controller for use in a power converter, comprising:
a first edge detection circuit coupled to receive a first input sense signal representative of an input of the power converter coupled to a dimmer circuit, wherein the first edge detection circuit is coupled to generate a first edge detection signal in response to the first input sense signal;
a shaping circuit coupled to receive the first edge detection signal from the first edge detection circuit, wherein the shaping circuit is coupled to generate a first shape signal in response to the first edge detection signal;
a drive circuit coupled to receive the first shape signal from the shaping circuit and a feedback signal representative of an output of the power converter, wherein the drive circuit is coupled to generate a drive signal in response to the feedback signal to control switching of a power switch of the power converter to control a transfer of energy from the input of the power converter to the output of the converter, wherein the drive circuit is further coupled to switch the power switch in a first higher current mode to increase a current through the power switch for a first duration in response to the first shape signal; and
a second edge detection circuit coupled to receive the first input sense signal, wherein the second edge detection circuit is coupled to generate a second edge detection signal in response to the first input sense signal,
wherein the shaping circuit is further coupled to receive the second edge detection signal from the second edge detection circuit, wherein the shaping circuit is coupled to generate a second shape signal in response to the second edge detection signal, and
wherein the drive circuit is further coupled to receive the second shape signal from the shaping circuit, wherein the drive circuit is further coupled to switch the power switch in a second higher current mode for a second duration in response to the second shape signal.

2. The controller of claim 1 , wherein the drive circuit is coupled to switch the power switch with at least one of a first increased frequency or a first increased duty ratio to increase the current through the power switch in the first higher current mode.

3. The controller of claim 1 , wherein the drive circuit is coupled to switch the power switch with a peak current threshold in the first higher current mode.

4. The controller of claim 1 , wherein the shaping circuit comprises a one shot coupled to receive the first edge detection signal, wherein the first shape signal is coupled to be responsive to an output of the one shot.

5. The controller of claim 1 , wherein the shaping circuit comprises:
a first comparator coupled to receive the first input sense signal, wherein the first comparator is coupled to compare the first input sense signal to a first threshold; and
an OR gate having a first input coupled to be responsive to the first edge detection circuit, and a second input coupled to be responsive to an output of the first comparator, wherein the first shape signal is generated at an output of the OR gate in response to the first edge detection signal or a comparison of the first input sense signal to the first threshold.

6. The controller of claim 5 , wherein the shaping circuit further comprises:
a second comparator coupled to receive the first input sense signal, wherein the second comparator is coupled to compare the first input sense signal to a second threshold, wherein the second threshold is less than the first threshold; and
a first pulse generator coupled to receive the first edge detection signal, the output of the first comparator, and an output of the second comparator, wherein an output of the first pulse generator is coupled to be received at the second input of the OR gate such that the first shape signal is generated at the output of the OR gate in response to the first edge detection signal or the output of the first pulse generator.

7. The controller of claim 1 , wherein the first edge detection circuit is coupled to generate the first edge detection signal in response to a detection of a leading edge of a half line cycle in the first input sense signal, and wherein the drive circuit is coupled to switch the power switch in the first higher current mode for the first duration during the leading edge of the half line cycle in the first input sense signal in response to the first shape signal.

8. The controller of claim 1 , wherein the drive circuit is coupled to switch the power switch at a first increased frequency in the first higher current mode, wherein the drive circuit is coupled to switch the power switch at a second increased frequency in the second higher current mode, and wherein the first increased frequency is greater than the second increased frequency.

9. The controller of claim 1 , wherein the shaping circuit further comprises a second pulse generator having a first input coupled to be responsive to an output of the second comparator, and a second input coupled to the second edge detection circuit such that the second shape signal is generated at an output of the second pulse generator in response to the output of the second edge detection circuit and the second comparator.

10. The controller of claim 1 , wherein the second edge detection circuit is coupled to generate the second edge detection signal in response to a detection of a trailing edge of a half line cycle in the first input sense signal, and wherein the drive circuit is coupled to switch the power switch in the second higher current mode for the second duration during the trailing edge of the half line cycle in the first input sense signal in response to the second shape signal.

11. The controller of claim 1 , wherein the first input sense signal is representative of an input voltage coupled to be received at the input of the power converter from the dimmer circuit.

12. The controller of claim 1 , wherein the first input sense signal is representative of an input current coupled to be received at the input of the power converter from the dimmer circuit.

13. A controller for use in a power converter, comprising:
a first edge detection circuit coupled to receive a first input sense signal representative of an input of the power converter coupled to a dimmer circuit, wherein the first edge detection circuit is coupled to generate a first edge detection signal in response to the first input sense signal;
a shaping circuit coupled to receive the first edge detection signal from the first edge detection circuit, wherein the shaping circuit is coupled to generate a first shape signal in response to the first edge detection signal;
a drive circuit coupled to receive the first shape signal from the shaping circuit and a feedback signal representative of an output of the power converter, wherein the drive circuit is coupled to generate a drive signal in response to the feedback signal to control switching of a power switch of the power converter to control a transfer of energy from the input of the power converter to the output of the converter, wherein the drive circuit is further coupled to switch the power switch in a first higher current mode to increase a current through the power switch for a first duration in response to the first shape signal; and
a dimmer conduction detection circuit coupled to receive the first input sense signal, wherein the dimmer conduction detection circuit is coupled to generate a dimmer conduction signal in response to the first input sense signal,
wherein the shaping circuit is coupled to receive the dimmer conduction signal from the dimmer conduction detection circuit, wherein the dr

Assignees

• Power Integrations Inc

Inventors

• Mao Mingming
• Pastore Tiziano
• Pregitzer Ricardo Luis Janezic
• Werner Antonius Jacobus Johannes
• Waterson Matthew David

Classifications

• H05B45/10

  Controlling the intensity of the light · CPC title

• H05B33/0815

  Electricity · mapped topic

• H05B33/0851 Primary

  Electricity · mapped topic

• Y02B20/30

  Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED] · CPC title

• H05B45/385

  using flyback topology · CPC title