Can anyone identify this National Semiconductor IC from an HP function generator? It’s either “M8942” or “M89421826” but I think the latter includes part of the mfr date codes.
Should be LM1826, but no datasheet.
https://www.machinio.com/listings/84356075-national-semiconductor-1826-0493-integrated-circuit-in-san-jose-ca
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Hello,
I could not come up with a replacement for this one.
Thanks! In the end I was able to find out it was an LM393. Appreciate the feedback!
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If you don’t mind could you explain how you figured that out?
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December 29, 2024 Troubleshooting my HP3314 Function Generator. (No +15V, or +5V)
A former coworker engineer friend helped me and was able to find the HP3314 Service Manual downloaded from here. Download HP 3314A Service Manual | ManualsLib
I had isolated to the failing circuit board (called A1) and the HOT unknown 8-pin DIP. With this huge service manual document, I was able to find the component diagram and identify it’s reference number as U805. Then I was able to find it on the schematic and could see that it was a comparator circuit.
After that, I found it on the BOM listed as an HP P/N 1826-0412. Luckily, a search on how to identify IC functions of HP part numbers, I found this link and identified it as an LM393.
Here:
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Thanks for the info
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That could be very useful for future searches, thanks for posting!