Reply by legg September 27, 20222022-09-27
On Tue, 27 Sep 2022 20:35:09 +0200, Johann Klammer
<klammerj@NOSPAM.a1.net> wrote:

>Specifically the LNK616 flyback regulator. >They have 1N4007 in their dataheets/appnotes. >But the 1N4007s trrs are all over the place. >Often around 1us. The regulator has a minimum on-time of >700ns, and really does not like surge currents. >What are better specced alternatives?
Slower diodes are used in the clamp for a reason. That said, I've never seen 4000 series specified there. In4937 (from memory) often used with trrs in the >500ns range. Don't use ultrafast parts there. Leakage energy is intended to be applied into the load during clamping, rather than being burnt. RL
Reply by Johann Klammer September 27, 20222022-09-27
On 09/27/2022 09:33 PM, Phil Hobbs wrote:
> Johann Klammer wrote: >> Specifically the LNK616 flyback regulator. >> They have 1N4007 in their dataheets/appnotes. >> But the 1N4007s trrs are all over the place. >> Often around 1us. The regulator has a minimum on-time of >> 700ns, and really does not like surge currents. >> What are better specced alternatives? >> > > How about > <https://www.digikey.com/en/products/detail/comchip-technology/US1M-HF/12713336> ? > > Cheers > > Phil Hobbs >
thank you.. forgot to say: it's all on perfboard. will use UF4007.
Reply by Phil Hobbs September 27, 20222022-09-27
Johann Klammer wrote:
> Specifically the LNK616 flyback regulator. > They have 1N4007 in their dataheets/appnotes. > But the 1N4007s trrs are all over the place. > Often around 1us. The regulator has a minimum on-time of > 700ns, and really does not like surge currents. > What are better specced alternatives? >
How about <https://www.digikey.com/en/products/detail/comchip-technology/US1M-HF/12713336> ? Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by Johann Klammer September 27, 20222022-09-27
Specifically the LNK616 flyback regulator.
They have 1N4007 in their dataheets/appnotes.
But the 1N4007s trrs are all over the place.
Often around 1us. The regulator has a minimum on-time of 
700ns, and really does not like surge currents.
What are better specced alternatives?