UCC28019A 1KW PFC

Quick calculations show that your 0.45mH inductor is a good choice and that your design should use a 0.02 Ohm current sense resistor.  But without the actual schematic or scope waveforms it would be impossible to speculate what the problem is.

What FET are you using?  Are you using a SiC diode?  The reverse recovery of the diode may be causing the failure if you aren't using an SiC.  Are you using a non-inductive sense resistor? Added ringing from parasitic inductance may be the issue. Is the heatsink adequate to keep the FET within its safe operating area?  The heatsink used on the EVM would not be appropriate for a 1kW design.  Does the FET fail at DC inputs less than 100V? Lower line voltage results in higher peak current; an AC input will have higher peak currents within each line cycle.

Dear LIsa,.Here is my schematic .

I use the SM6A09NSFPC-TUG for the PFC MOS and ETF1606CT for PFC DIODE.

I replace the mos with K6A60D ( Tobshiba product) and it works OK . I guess it is not current issue 

Maybe the Diode is the isssue .

Thanks a lot .

Dear Lisa ,

Here comes new issue today .

Good new MOS did not burn now .

I add the loading ( output resistance is 280Ω，about 500W) the PFC output Voltage drop to about DC 158V

I measure the PWM duty Cycle is 18.4us and the duty is 2.8us .

My issue is Why or how UCC28019A makes the duty small?

PIN 4 is 1.7V

Pin 6 is almost  0.

Where should I need to check ? 

Are you using a separate well-regulated 12VDC supply for VCC?  I did not see the schematic attached; try attaching it again.  Pin 6 will be pulled low during an open-loop detection fault.  First check your soldering.   

Dear Lisa,

1. VCC is good regulated at 12.56V ripple is about 50MV

2. Pin 6 should be input Pin , not output Pin .

What you mention should be Pin 5 (VCOMP).

I add a 500W load and the board has a spike noise ( I can not observer where is the spike )。D you have any idea where should it have the change to  have the spike ?

Thanks you LIsa .

Dear Lisa,

I measure the Pin 5 of UCC28019A and the voltage is 2.4V( with loading 280Ω)PFC Output Voltage is DC 390(with no Load).

PFC Output Voltage is DC 161 V input is AC 110 V

I have two board . one can add the load 500W , no problem ( with one MOS ) and will burn with two MOS)

Do you have any opinions about that ?

Best regards,

Edward Wu

Dear Lisa,

May I modify the UCC28019AEVM and make it work to 1KW PFC .

1. Boost inductor  1.25mH to 0.45MH

2.20A MOS to 25A MOS 

what else I need to change to make it work at 1KW PFC ?

You need to run the design calculator to verify all of the other components are applicable to your requirements.  I don't think the heatsink is robust enough, the compensation may need changes, etc.  EVMs are designed specifically for the application stated in the electrical specification and we don't design a lot of "padding"...a 350W design will not accommodate a 1kW application without changes.

Dear Lisa,

Thanks for your reply.

I have one issue .

I use my board , but I can only add loading up to about 500W , Over 500W the PFC Output Voltage will drop .

What's going on ?

Voltage issue or else ?

By the way , would descrip how UCC28019A works ?

1. Voltage loop 

2. Current loop .

3. How to handle the PWM duty ?

Thanks a lot.

Best regards,

Edward wu

Sky account : edwardwu

Dear Lisa,

I did some UCC28019AEVM testing . 

I can add the load up to 750W and the EVM still worked ,( not for long time)

It is really different than our board .

I have one question . if over lod, what EVM board   behavor ? drop the output voltage or else?

Because the current loop compensation or protection!, how does it works?