Re: tiny dc/dc

john larkin <jl@glen--canyon.com> wrote:

On Fri, 28 Mar 2025 16:49:23 -0400 (EDT), Martin Rid
<martin_riddle@verison.net> wrote:
 

john larkin <jl@glen--canyon.com> Wrote in message:r

Check out UCC33420. It's a tiny cheap isolated dc/dc converter. It switches at 64 MHz!

 
Why does it have such poor esd ratings?
The ucc33421 is better, but not 15kv.
Cheers

 
Right now I dodn't need kilovolts of isolation. I want to make a GaN
totem-pole driver and want a floating power supply for the high side,
but I want very low switching noise for low jitter on the rising edge.
 
I might try one of these with a bunch of added filtering. It might be
better than some dc/dc that works in the 100 KHz sort of ballpark.
 
Or it might be much worse.

I bet the gain bandwidth of a GaN FET in its linear range at high current
is pretty impressive.

I’m using SiGe BJTs to speed up the edges of my TDR pulse generators.
Driven from a 500-ps comparator edge, it’s fast enough to oscillate on the
falling edge if the layout isn’t right.  That’ll make really entertaining
jitter.

Cheers 🍻

Phil Hobbs

--
Dr Philip C D Hobbs  Principal Consultant  ElectroOptical Innovations LLC /
Hobbs ElectroOptics  Optics, Electro-optics, Photonics, Analog Electronics