UCC28070: Hello, i'm trying to make an AC/DC pfc correction converter with UCC28070pwr. I make PCB attached you can see my problem is that ucc28070 controller Vsense

Dogan Birdal

Part Number: UCC28070

I make PCB attached you can see my problem is that ucc28070 controller. Vsense pin voltage is decrease 2.5 volt and i can't increase to 3 volt. Controller is not enabled and doesn't give output PWM. Can you plase check my shmetik diagram and have look why controller is not enabled and controller keep Vsense to 2.5 volt? Interleaved_v5.pdf

over 5 years ago

0 John Griffin1 over 5 years ago

TI__Mastermind 34465 points

What is the voltage on the VINAC pin ?

0 Dogan Birdal over 5 years ago in reply to John Griffin1

Prodigy 180 points

VINAC=2 Volt, Vsense=2.5 volt. Vref=6 volt, PKLMT= 3.8 Volt. But controller GDA and GDB doesn't give PWM.

0 John Griffin1 over 5 years ago in reply to Dogan Birdal

TI__Mastermind 34465 points

I do not see an issue with your schematic and you should have a pwm signal with the VSENSE and VINAC signals above..

Check that your pcb is connected as in the schematic. It may be there is an error in the construction or it may be the UCC28070 is damaged.

Regards

John

0 Dogan Birdal over 5 years ago in reply to John Griffin1

Prodigy 180 points

I changed controller many times the result doesnt changed. In controller Dmax and RT pin controller gives PWM wave form 2.8 volt. As i know it should be dc voltage not pwm Do you have any idea about this behave?

0 John Griffin1 over 5 years ago in reply to Dogan Birdal

TI__Mastermind 34465 points

Yes.
As I said, examine your breadboard or pcb and check all of the connections.
There is a reason why this is not working and the reason is not shown in your documentation and can only be found by discovering the
discrepancy between the documentation and the actual implementation.
Good Luck with your quest.

Regards

John

Power management

Power management forum

UCC28070: Hello, i'm trying to make an AC/DC pfc correction converter with UCC28070pwr. I make PCB attached you can see my problem is that ucc28070 controller Vsense