On Thu, 08 Oct 2020 08:23:08 -0400
legg wrote:

On Wed, 7 Oct 2020 19:49:14 +0100, Roger wrote:

On Wed, 07 Oct 2020 10:51:22 -0700
Jeff Liebermann wrote:

On Wed, 7 Oct 2020 16:53:26 +0100, Roger wrote:

Hi, I'm hoping that someone out there will have some info on an
ON Semiconductor 5105FA

Not exactly what you were asking:
https://www.onsemi.com/products/discretes-drivers/mosfets/ntr5105p
If you inscribe "5105" in the search box, you'll get a list of
other possible matches.

It would be very helpful if you would describe the package,
application, and provide a photo. I don't think you're reading the
part number or manufacturer correctly.


It's on a dashboard PCB from a Lincon Navigator, it seems to be a
one of a identical pair of switchers driving a transformer primary.
Here's an identical one to mine:

http://www.tehnari.ru/f39/t256954/

Thanks.

Board markings indicate a bipolar transistor.

I'm guessing ~TIP31B, based on the other body
marking.

I've hit a blank everywhere else, so a suck-it-and-see lucky guess
substitution attempt is my next move. I've got some TIP31Bs - I'll let
you know if your guess wins ;-)

Cheers.