7 Nov
2005
7 Nov
'05
7:06 a.m.
2) It's shut down. The shutdown pin is driven from
the SCR CR11 on the
1144-01E PCB. That takes inputs from the current sense circuit and the
overvoltage shutdown. Since you say that the shutdown pin is not asserted
(do check this at the 'other' side of R11, 6k8), I think this is not the
problem weeither.
I was in error, the 3524 is shutdowned (lessical correct? :))
After a short time (during this outputs are available) the signal on R11
goes high, blocking 3524
Now I try to understand if is current overload or voltage protection circuit
that become active.
Alberto
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Alberto Rubinelli Mail : alberto at a2sistemi.it
A2 SISTEMI Web : www.a2sistemi.it
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http://www.retrocomputing.net
ICQ : 49872318 Skype : albertorubinelli
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