surface mount device codes
has any body got any idea what a surface mount device is with marking GFN 38 and also a diode symbol with its legs wrapped around to form a capital S. the device is 7mm long 5.5 mm wide and 2 mm deep, the two connections are on the short ends. it measures 4 ohms. It is in a dog perimeter minder circuit board , no bar marking on either end . just the symbol and text . the low value of ohms is causing over current draw on the 12 volt supply . i have extensive google search with no success . removing the device from the board has solved the problem and it appears to work correctly . but mave not tried it with the dog collar.
Thanks for assistance in advance.
Thanks for assistance in advance.
d-glitch
Presumably the circuit was working, then it stopped working, and you noticed the suspect part was getting hot. I think what you have is a failed protection diode. The circuit will work fine without it, but it will be at increased risk of damage from line voltage surges.
I believe FN means Flat No-Lead.
However I can't get any further than that.
However I can't get any further than that.
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Thanks. That isn't the official logo for ST, but they would probably be irked if another company used that mark.
I'll resume the search there.
I'll resume the search there.
ASKER
If there is no further comment , i think i will put it back into service and hope there are no surges. thanks for looking , I have had no further success either.
I have looked at the ST website and found more than a hundred of these parts with 3-letter codes, but none of them is a match for yours. Some of the relevant data sheets are attached. The 3-letter codes are on page 8. The middle letter is always U or B (for unipolar and bipolar). And the logo looks different too.
CD00001333.pdf
CD00001366.pdf
CD00001333.pdf
CD00001366.pdf
ASKER
I chose one of the vishay bidirectional devices as they were the same dimensins . i have put it in the pcb and returned it to the customer and it is working ok. Thanks