help requested from electronics components wizards - T518A voltage detector

shardian

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help requested from electronics components wizards - T518A voltage detector

Took my Lethal Weapon 3 CPU over to a friend's to do some testing. After looking at the acid damaged blanking section, it became obvious IC1 was bad. So bad in fact, that it fell right off the legs were so badly corroded.

What is it? It is a T518A voltage detector.

This may or may not have been the problem. We shorted the outer two leg nubbins on the board together to simulate a closure, but didn't see a change in the power LED's.

Why do I need help? Because I can't seem to find a source for a replacement.
 
Thanks!

Ah man...I only need that one teeny tiny part. I hate this aspect of electronics repair. I'm going to end up spending more on shipping than a replacemtn board would cost!
 
This may or may not have been the problem. We shorted the outer two leg nubbins on the board together to simulate a closure, but didn't see a change in the power LED's.

I'm not where I can pull up a the DE board schematic, So I don't know exactly how it's used, But if I recall that device is usually used as a voltage threshold detector, often to drive a reset circuit. The output of the device is actually a sink, not a supply. When Vcc reaches the designed voltage (usually somewhere around 4.4vdc), the IC internally connects "OUT" to "GND".

In a nutshell, you don't want to jumper pins 1 (Vcc) to 3 (out), depending on the application, that could actually damage something else on the board. To jumper the device and simulate what it would normally do, connect pin 2 (GND) to 3 (out).

My old memory might be failing me here, so I could be wrong, but might be worth looking at the datasheet and board schem before trying anything else to simulate the IC's function.

D
 
This is in the blanking circuit. We assumed it acted as a gate for the +5. I guess that's what we get for trying a last ditch effort in stoppage time on a lunch break. ;)

Hopefully nothing else went bad. by bridging 1 and 3.
 
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