[vcf-midatlantic] Can anyone identify this mystery IC

[Douglas Crawford]

They are changing their tune, Dave :)

One says:
" Metalization is hiding all the lower levels. Looks like a device with 
just 6 transistors."
Another responds:
"So it would be a *transistor* array, not a gate array then.
If so, then I’m confused as to why it would need so many pins if there 
are only 6 transistors.  Unless it was a prototyping part where all the 
transistors were individually made accessible."

(I'm positing with them # pins is because possibly they're gates)




On 8/21/2022 12:50 PM, Dave McGuire via vcf-midatlantic wrote:
> 
>    Yes, but we should be able to determine everything, or almost 
> everything we need to know from that layer.  We'd need better and 
> higher-resolution photos.
> 
>               -Dave
> 
> On 8/21/22 12:48, Douglas Crawford via vcf-midatlantic wrote:
>> Ah, now we are getting somewhere.
>> We can only guess then, from the remaining metalization layer
>> correct?  Educated guess?
>>
>> On 8/21/2022 12:43 PM, Dave McGuire via vcf-midatlantic wrote:
>>> On 8/21/22 12:39, Douglas Crawford via vcf-midatlantic wrote:
>>>> These are the transistors?
>>>> https://imgur.com/aLpqVpE
>>>
>>>    I'd need to look more closely, but those appear to be clusters of 
>>> transistors, six of them.  They are likely gates.
>>>
>>>> I got one additional response from another designer:
>>>> "Looks like some kind of gate array with only the metalization layer 
>>>> being clearly visible. I worked on alot of these in the late 70's. I 
>>>> have no explanation for the bonding pad structures."
>>>
>>>    Agreed; this has either had its passivation layer removed, or it 
>>> had never been applied.  I suspect the latter, as it would've been 
>>> removed with acid, and there isn't so much as a trace of debris from 
>>> that.
>>>
>>>              -Dave
>>>
> 
>