WTB: Agilent 1822-0639 GPIB chip for 34970A - Page 1
Forum section: electronics / general

author: Jwalling
author_rank: Unknown
timestamp: July 22, 2016, 03:34:21 pm
content: Looking for one of these to complete a repair on a 34970A. Agilent won't sell them. The find-a-part website description is NFTS IC ASIC HPIB Controller, Keysight Trade Restricted. Not orderable, Contact Keysight for repair service. Trade secrets?Bastards.I'm quite leery of shopping here for it:http://www.aliexpress.com/w/wholesale-1822%25252d0639.html?spm=2114.01010208.0.51.UcXmBE&site=glo&g=y&SortType=total_weight_score_desc&SearchText=1822-0639&initiative_id=SB_20160721081927&shipCountry=US&needQuery=nThanks.Jay

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: July 22, 2016, 04:36:11 pm
content: Hi Jay,This info may help. The part is used in the HP6653A, and the CLIP is available.The schematic shows:And the parts list shows:This suggests that it a TMS99C14 chip. You might be able to tell from the board.Regards,Jay_Diddy_B

author: Jwalling
author_rank: Unknown
timestamp: July 22, 2016, 05:05:00 pm
content: Quote from: Jay_Diddy_B on July 22, 2016, 04:36:11 pmHi Jay_Diddy_B,Interesting. Must have beenhttp://www.onsemi.com/PowerSolutions/content.do?id=16667Looks like Onsemi ditched the GPIB parts if so.Weird that the 6653A BOM and schematic differ as does the 34970A.Seehttps://www.eevblog.com/forum/repair/agilent-34970a-gpib-controller-chip/I do have some PLCC TMS99C14 chips on a couple of scrap 34401A boards, but note Kleinstein's reply to my post, so not sure if they would work or not... If I get desperate, I may beep out the entire GPIB chip on my 34970A and see if it matches the schematic in the service manual which also shows a TMS99C14. If it does, I'll probably take the chance and swap it.Thanks for that!EDIT:Then there is:https://www.eevblog.com/forum/beginners/gpib-getting-started/msg783535/#msg783535Hmm. ON Semi 14063-501 (Crap no datasheet on that either)and:https://www.eevblog.com/forum/testgear/flood-of-new-agilent-82357b-gpib-usb-adaptors-on-ebay-the-real-deal/msg751345/#msg751345Hey! That's me!Jay

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: July 22, 2016, 10:14:07 pm
content: Hi Jay,I would have a go at buzzing it out. I think that the story is like this:1) TI stopped making the TMS99142) HP made an ASIC (1822-0639) to replace it, I don't know if it is pin compatible, I suspect it might be.It may also be worth checking the NAT9914, this was engineered by NI around the same time. It is used in the Keithley 2001 (among others).Link:http://sine.ni.com/nips/cds/view/p/lang/en/nid/11153Regards,Jay_Diddy_B

author: woodchips
author_rank: Frequent Contributor
timestamp: July 23, 2016, 10:38:21 am
content: The circuit is missing 5 pins, 1, 10, 18, 28 & 40 so more than likely a simple repackage into plcc of a dip part?For what it is worth the 2670 uses gpib chip 1820-2549 which is 40 dip, and the thinkjet printer (02225 marked on pcb) uses the 1LH4-001 gpib chip 40 dip. That looks like a gate array part number?

author: Jwalling
author_rank: Unknown
timestamp: July 24, 2016, 05:43:21 pm
content: Success! The TI part works fine.Seehttps://www.eevblog.com/forum/repair/agilent-34970a-gpib-controller-chip/msg989827/#msg989827EDIT: Thanks all!Jay