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#373924 - 30/10/2022 20:12 What is it? (chip)
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14414
Loc: Canada
What is this chip?
Based on context, I'm guessing some kind of NAND gate/buffer.

Pin-1 is hardwired to Pin-7.
Pin-2 is grounded.
Pin-3 is the output where the processed input from Pin-1 exits the chip.
Pin-4 is GND.
Pin-5 is the input of interest.
Pin-6 appears to be another input of interest.
Pin-7 is hardwired to Pin-1.
Pin-8 is +5V.


Attachments
chip.jpg

Description: Unknown 8-pin SOIC




Edited by mlord (30/10/2022 21:36)

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#373926 - 30/10/2022 21:43 Re: What is it? (chip) [Re: mlord]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14414
Loc: Canada
So, wired like this. The input signals are 3.3V logic, and the chip outputs 5V logic.


Attachments
hand-controller-TX.jpg



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#373927 - 30/10/2022 22:00 Re: What is it? (chip) [Re: mlord]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14414
Loc: Canada
I'm guessing at something like a Dual 2-input NAND gate, with open-drain outputs: https://assets.nexperia.com/documents/data-sheet/74LVC2G38.pdf

Just need to identify the exact part.

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#373928 - 01/11/2022 18:25 Re: What is it? (chip) [Re: mlord]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31501
Loc: Seattle, WA
I don't have an answer for you but I love how this is the EmpegBBS version of https://www.reddit.com/r/whatisthisthing/
_________________________
Tony Fabris

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#373929 - 03/11/2022 08:31 Re: What is it? (chip) [Re: mlord]
peter
carpal tunnel

Registered: 13/07/2000
Posts: 4165
Loc: Cambridge, England
HD74LV2GT125AUS dual bus-buffer with 3-state output, or compatible?

https://www.renesas.com/us/en/document/dst/hd74lv2gt125a-rej03d0148-0200z?language=en&r=527771

Found via https://smd.yooneed.one/

Peter

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#373930 - 03/11/2022 13:12 Re: What is it? (chip) [Re: mlord]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 14414
Loc: Canada
The HD74LV2GT125AUS doesn't match the pin-out unfortunately, but a 74LVC2G38 does match and is probably the part.

As it turns out, the failure was in another chip just upstream of of it. A teensy tiny 8-pin + GND chip about the size of a grain of sand. Turned out to be a 4ch ESD protection device, which makes sense -- it failed and protected the rest!

Thanks all!

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