Single Stage PFC Flyback Choices for CV Output

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I have a specialized LED lighting application that requires:


Power Output Range for various designs: 6-10W

Very high PF: > 0.968

Full range dimming using microcontroller PWM dimming: 0 - 100%

Output Isolation is preferred


Not to mention, I also need a housekeeping supply to operate the microcontroller from.


I have experimented with the LinkSwitch PH and PL devices, implementing some of the designs outlined in the App notes and document DER-263.  My conclusion is that I am not going to achieve everything that I want from a Single Stage design.  My current plan is to implement a low-power PFC Flyback design with a CV output and use this to operate the microcontroller and also power a separate, discrete CC LED regulator with PWM dimming.


Looking through the available PI devices and applications however, I don't see where any low-power PFC Flyback designs have been implemented other than the LinkSwitch PH and PL designs.  I was thinking along the lines of a design using something like the LinkSwitch CV devices.


I suppose I could convert a LinkSwitch PH design to CV operation.  I just wonder if there is something that I am overlooking?   Has someone actually achieved a LinkSwitch PH design with 0-100% PWM dimming, with an integrated housekeeping supply for microcontroller operation?  Can someone give me a pointer for a device or App Note for a low-power PFC Flyback design with CV output?


Thanks in advance

LinkSwitch PH does not work with CV operation.

DER-263 I believe is the only available pwm dimming design example you can use as reference on your design.

For PFC flyback design with CV output, you may use LinkSwitch-CV with passive power factor using Valley Fill Circuit.