UCC38C43 and UC3843: can I use the first one without problems?

[Frank Zampa]

Dear Sirs, I would like to replace the TI UC3843 with the UCC38C43.

My objective is to reduce the thermal power dissipation in the control
zone in a flyback SMPS, and the five-time supply current reduction of
the UCC38C43 is very interesting.

This new IC seems more sensible to the edge spikes associated with the
turnon of the main power MOSFET, specially at the current sense pin.

My qualm is that the UCC38C43 is a new IC, not so tested like the
UC3843.

Does someone use the UCC38C43 with satisfaction and without problems?

Could you give me some advices?

Thanks, Frank Zampa.

 

[Winfield Hill]

Frank Zampa wrote...

Dear Sirs, I would like to replace the TI UC3843 with the UCC38C43.
My objective is to reduce the thermal power dissipation in the control
zone in a flyback SMPS, and the five-time supply current reduction of
the UCC38C43 is very interesting.

This new IC seems more sensible to the edge spikes associated with the
turnon of the main power MOSFET, specially at the current sense pin.

My qualm is that the UCC38C43 is a new IC, not so tested like the
UC3843.

Does someone use the UCC38C43 with satisfaction and without problems?

I've used other parts in the ucc CMOS family, and they've worked
very well. The ucc38c43 is a three-year-old or older part, and is
in production at the 20k/month level, according to TI's web site,
so clearly many others find it working well for them. DigiKey has
them in stock, at $2.13 each, and $1.275 qty 100.

Thanks,
- Win

whill_at_picovolt-dot-com