23 Jan
2017
23 Jan
'17
11:07 a.m.
On Mon, Jan 23, 2017 at 6:48 PM, Adrian Graham
<witchy at binarydinosaurs.co.uk> wrote:
On 22/01/2017 20:10, "Tony Duell"
<ard.p850ug1 at gmail.com> wrote:
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
components
around? It might be one of the special SMPSU ICs, but it doesn't
instantly ring a
bell with me.
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
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?
-tony