Replacement nvram clock chip for Atlas 550

[redlineken]

We have quite a few 550s whose onboard clock/config battery (DS14287) has expired.  As mentioned in this thread Atlas 550 Loses Config the Dallas chip has long been obsolete and its suggested replacement (BQ4287MT-SB2) is now also obsolete.  What chip does Adtran use when someone sends in a unit for repair?   We also have several other Atlas models (800, 830 and 890).  Does anyone know if they use the same clock battery or do they use a coin-type battery (CR2032, etc.)?  I can't take those units out of service to investigate.  Thanks.

-Ken

[jayh]

The chips are available from a few suppliers. They are a piggyback type chip. It's a regular 24-pin wide DIP with a coin battery atop it potted with epoxy into a module that is taller than a conventional DIP. Adtran has soldered them to the PC board, so to repair you will need to be comfortable with through-hole component level repair. Observe static precautions. I would strongly suggest replacing the bad chip with a socket and plugging the new chip into the socket. Some have had success with digging out the potting compound and replacing the sealed battery within the defective chip. Make sure to note the orientation of pin 1 of the chip. See video linked below.

New chips still available (and sockets): http://www.epower2go.biz/catalog/index.php?main_page=index&cPath=9

Video of repair of existing chip: https://www.youtube.com/watch?v=NdlSfqto_0o

You will need to take the units out of service to repair. There isn't a practical way to retrofit with a replaceable battery other than atop the old chip as shown in the video.

[ggiesen-egate]

Sorry to dig up a very old thread, but we went looking for options here and I've ordered a few of these:

https://github.com/necroware/nwX287

They're available pre-made from a few sellers, and advertises DS14287 compatibility (you'll have to clip a few pins). It comes with a holder for a CR1225 battery so hopefully will be the last replacement, once installed.

I haven't received them yet but I'll report back on whether we're successful or not.

[ggiesen-egate]

We've installed the nwX287 (along with a socket - had to clip the pins on the socket too) and it appears to be working perfectly.

We bought the premade units from https://www.pcptech.es/p/nwx287-dallas-ds14287-benchmarq-bq4287-replacement-repuesto-recambio (they also have an eBay listing - https://www.ebay.com/itm/314771014092). Make sure you get the DS14287/BQ4287 version.