Transformer part ID please

Tony Duell ard.p850ug1 at
Mon Jan 23 13:07:03 CST 2017

On Mon, Jan 23, 2017 at 6:48 PM, Adrian Graham
<witchy at> wrote:
> On 22/01/2017 20:10, "Tony Duell" <ard.p850ug1 at> wrote:
>>> That looks like an opamp to me, with bias pins connected to GND?
>> Does it? It looks like a 555 timer to me at first glance. I would have
>> expected another
>> capacitor from pins 2/6 to ground though.
>> 1 Ground
>> 2 Trigger (linked to threshold, and to output via a timing resistor)
>> 3 Output (driving the MOSFET)
>> 4 Reset/ (pulled high via a resistor)
>> 5 Control Voltage (decoupled to ground)
>> 6 Threshold (see 2)
>> 7 Discharge (not used here)
>> 8 Vcc
> I didn't think of a 555 in that scenario but that makes sense. I've marked
> it as such for now, cheers!

Is there another capacitor from the 2/6 junction to chassis? Any other
around? It might be one of the special SMPSU ICs, but it doesn't
instantly ring a
bell with me.

> Tonight it's 'address pins and why I get inconsistent results on a logic
> analyser while looking at everything that touches A7' :)

Short from A7 to another pin? Failed address latch?


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