Fairchild part numbers trivia following.
On 2020-Jul-28, at 7:35 AM, Jay Jaeger via cctalk wrote:
> My DTL chips have markings like:
>
> DT uL93659 (Chip type 936)
> F 7016
>
> DT uL909759 (Chip type 9097)
> F 7013
>
> (I expect 7016 and 7013 are date codes. Not sure what the "59" is about.)
The 59 is the temperature range. For DTµL, 59 is 0C::+75C.
On 2020-Jul-28, at 8:11 AM, Paul Koning via cctalk wrote:
>> On Jul 28, 2020, at 10:35 AM, Jay Jaeger via cctalk <cctalk@classiccmp.org>
>> wrote:
>>
>> DT uL93659 (Chip type 936)
>> F 7016 ...
>
> Is that DTL or RTL? Fairchild originally came out with RTL chips, which had
> uL part numbers like uL914 (dual 2 input NOR) and uL923 (JK flop) in TO cans
> with 8 leads.
The 936 is DTL.
Fairchild part numbers were a bit of a mess when looked at over their
production period.
The part numbers did not readily distinguish between logic families.
Some units had the RTµL/DTµL/TTµL labeling, but that was not always present
(the Fairchild labeling there actually is mu/micro rather than u).
Some examples of the mish-mash:
901 : RTµL
915 : RTµL
926 : RTµL
936 : DTµL
946 : DTµL
960 : CµL
961 : DTµL
9007 : TTµL
9097 : DTµL
9997 : RTµL
There was often an additional 9 in front of the 3-digit types.
e.g. 9936 is DTµL 936.
Even the 59 suffix for the temp range, mentioned above, was ambiguous.
59 meant 0::+75C for DTµL, TTµL & CµL,
but
59 meant +15::+55C for CTµL.
> The supply voltage would tell you; RTL uses 3.6 or so, while DTL uses 6 volts.
Per the OP's machine, the early HP21xx machines were based on CTµL, for which
the main supply is +4.5V.
DTL and TTL chips in these machines ran off that 4.5 supply.
