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General => General Technical Chat => Topic started by: Alex Eisenhut on August 14, 2024, 01:08:14 am

Title: Can part numbers be used twice by the same manufacturer?
Post by: Alex Eisenhut on August 14, 2024, 01:08:14 am
Playing around with a dead HP Kittyhawk hard drive, a tiny drive from 1992.
There is a Philips TDA5340 chip in a 48 pin TQFP.
However that part number gets me a part in a different package and obviously not the right function. Some sort of radio transmitter.

Closest I could find is TDA5345HT, a spindle and voice coil driver, but in a larger pin count package, but the description fits. It's right next to the connector that goes to the drive itself.

Did they just reuse a part number?

It's hard getting any data for most of the chips on this little paperweight.
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: fzabkar on August 14, 2024, 01:58:44 am
I found a TDA5341, also in a larger pin count:

https://pdf.datasheetcatalog.com/datasheet/philips/TDA5341G.pdf (https://pdf.datasheetcatalog.com/datasheet/philips/TDA5341G.pdf)
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: ebastler on August 14, 2024, 08:59:27 am
Is it the same manufacturer? The TDA5340 wireless chip seems to be from Infineon (2012). I was not aware that they have (or had, back then) acquired parts of the Philips/NXP portfolio?
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: Alex Eisenhut on August 14, 2024, 02:02:18 pm
Oh yeah, I though Philips became Infineon. Didn't check twice I guess. So in that case I just can't find a datasheet.
Oh well. Must be a part only for this little HP drive...
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: tooki on August 14, 2024, 11:13:57 pm
Playing around with a dead HP Kittyhawk hard drive, a tiny drive from 1992.
There is a Philips TDA5340 chip in a 48 pin TQFP.
However that part number gets me a part in a different package and obviously not the right function. Some sort of radio transmitter.

Closest I could find is TDA5345HT, a spindle and voice coil driver, but in a larger pin count package, but the description fits. It's right next to the connector that goes to the drive itself.

Did they just reuse a part number?

It's hard getting any data for most of the chips on this little paperweight.
I found this tiny bit of info:
https://archive.org/details/edn-1992_07_20/page/n21/mode/2up?view=theater

Looks like the TDA5341 fzabkar listed is closely related.
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: rsjsouza on August 14, 2024, 11:49:44 pm
I found the information below on a somewhat obscure website that wants you to register to download its datasheet.

The IC description is shown as "motor solenoids", which seems innacurate but still somewhat close enough to be  applicable to HDDs.

http://www.ecadata.de/ddv/mysucheca.php?F_SPRACHE=2&NFIRST=0&ECA_KEY=TDA5340&select=&F_USERNAME=&F_PASSWORT=&ECA_DEF=&ECA_ABC=&F_KUNDNR= (http://www.ecadata.de/ddv/mysucheca.php?F_SPRACHE=2&NFIRST=0&ECA_KEY=TDA5340&select=&F_USERNAME=&F_PASSWORT=&ECA_DEF=&ECA_ABC=&F_KUNDNR=)

Good luck!
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: amyk on August 15, 2024, 12:41:53 am
Here is a patent that mentions the TDA5340 motor driver: https://patentimages.storage.googleapis.com/dd/32/af/44b4e0f9487e8f/EP0573964B1.pdf

Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: Kleinstein on August 15, 2024, 06:42:50 am
They should not reuse the part number. As one odd case where they did it is with the LM321, that was originally a somewhat odd precision amplifier and some company also use that number also for a single OP-amp as LM358/324 equivalent.

The predecessor to Infineon was the semicondictor part of Siemens. Phillips changed to NXP, but that was much later.
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: fzabkar on August 15, 2024, 07:30:25 am
Playing around with a dead HP Kittyhawk hard drive, a tiny drive from 1992.

It's hard getting any data for most of the chips on this little paperweight.

Some brief info ...

https://mirrorservice.org/sites/www.bitsavers.org/components/att/1993_ATT_Microelectronic_Products_Selection_Guide.pdf (https://mirrorservice.org/sites/www.bitsavers.org/components/att/1993_ATT_Microelectronic_Products_Selection_Guide.pdf) (page 31)

https://mirrorservice.org/sites/www.bitsavers.org/components/att/1993_ATT_Storage_ICs_91c010-12_20.pdf (https://mirrorservice.org/sites/www.bitsavers.org/components/att/1993_ATT_Storage_ICs_91c010-12_20.pdf)

http://www.nixiebunny.com/kittyhawk/kittyhawk.html (http://www.nixiebunny.com/kittyhawk/kittyhawk.html) (photos)

https://mirrorservice.org/sites/www.bitsavers.org/components/cirrusLogic/_dataSheets/ (https://mirrorservice.org/sites/www.bitsavers.org/components/cirrusLogic/_dataSheets/)
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: fzabkar on August 15, 2024, 05:16:11 pm
I was looking at the PCB and I couldn't find any SRAM or DRAM, and none of the ATT ICs contain anything more than 256 bytes. So where is the sector buffer? Is it in the CL chip?
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: Alex Eisenhut on August 15, 2024, 05:46:58 pm
I found all those as well, but it's pretty limited. Oh well, just another paperweight I guess.
Title: Re: Can part numbers be used twice by the same manufacturer?
Post by: tooki on August 16, 2024, 02:34:23 pm
They should not reuse the part number. As one odd case where they did it is with the LM321, that was originally a somewhat odd precision amplifier and some company also use that number also for a single OP-amp as LM358/324 equivalent.

The predecessor to Infineon was the semicondictor part of Siemens. Phillips changed to NXP, but that was much later.
Hah, that is weird! National Semiconductor made the LM321 precision preamplifier first, but they themselves also sold the LM321 op-amp!

I suspect that some second-source manufacturer which made cloned LM324s independently came up with LM321 (maybe even based on the LM324?) and didn’t realize that number already existed as an obscure NatSemi part. And then later NatSemi discontinued their LM321 preamp and later still introduced their second-source LM321 op-amp.

It’s kind of a miracle that we don’t have a lot more part number collisions than we do, given that there’s no central registry or the like.