Hey all,

I have an IC that takes input from a computer and outputs two high voltage sine waves. The input determines the frequency of the sine waves (are about 40-50 kHz). I've attached a picture of one part of the circuit that I'm having a bit of difficulty understanding. A uC is connected to a DAC, which is eventually connected to a PLL. I don't get what the blue things (pots?) or yellow things are (I've marked them in the picture). I'm trying to understand what is going on from the DAC to the PLL. I'd appreciate any insight or advice!


-d02

 

The upper blue pot is marked 504, which means 50 with 4 zeros after, or 500k Ohms.
The lower blue pot is marked 503, or 50k Ohms.
They may be 10- or 21-turn trimpots.

I can't make out the part numbers on the yellow rectangular devices.

 

This yellow rectangular devices maybe some kind of opto-isolator.

 

The first thing that comes to mind when seeing the two "yellow things" is that they are optocouplers. Maybe... Just a thought.

It looks like the bottem line of the part is 825P281...

Edit: Most of the 825 parts seem to be dual optos in larger packages though...

 

Well, here's a link to Vishay's K825P datasheet:
http://www.vishay.com/docs/83524/83524.pdf

It might could be a K825P with the leads snipped short.

 

Hey all,

Thanks for the quick reply. There are a couple of step up transformers on the board that I'm having trouble identifying. There aren't any markings that I can see. I don't really understand the pinouts... there are (from what I can tell) 6 input pins on the low side and 8 on the high side. Please see the attached picture. Are there any data sheets for the same/similar transformers?

 

Hey all, sorry to bump this up, but I'm still having a lot of difficulty ID'ing this part. I generally look on places like Digikey. Does anyone have any suggestions?

 

Components like transformers are much harder to identify without additional clues. They could be custom made for the product so their specifications may not be public.