IBM 5155 Power supply schematics or info

[Alberto Rubinelli - A2 Sistemi]

> 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
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