Thread: Zx81
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Old 27th Mar 2020, 3:23 pm   #207
Slothie
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Join Date: Apr 2018
Location: Newbury, Berkshire, UK.
Posts: 1,287
Default Re: Zx81

Quote:
Originally Posted by John Earland View Post
Regarding the ULA on the ZX81, this might be a silly question but why does heat cause it to fail? Normally it’s fine until it gets warm/hot.
If there is a tiny crack in the silicon or between the gold bond wire and die in can contact when cold, and when it heats the silicon and aluminium on the chip expand at slightly different rates bending the chip slightly opening up the gap. The gap only has to be a few molecule wide to stop the electrons!

Last edited by Slothie; 27th Mar 2020 at 3:24 pm. Reason: Autocorrect failure
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