On Thu, 08 Mar 2007 19:24:06 GMT, John E. put
finger to keyboard and composed:

The part that has failed has these markings:

LS1176
8AT
D5HT

This is the data sheet for it, I think:

SN65ALS1176:
www.cgi/http://www.allcomponents.ru/pdf/ti/sn65als1176.pdf

This is TI's page:
http://focus.ti.com/docs/prod/folder...65als1176.html

This is TI's search page:
http://focus-webapps.ti.com/general/...archdevice.tsp

although how to I tell if the failed one is a 65 or 76 prefix part?

Searching for parts containing "LS1176" at TI's web site finds only
the SN65ALS1176.

Searching local suppliers, I find this:

SN75LBC176A:
http://www.jameco.com/Jameco/Products/ProdDS/251053TI.pdf

Is the second a suitable replacement for the first?

See TI's documentation:
http://focus.ti.com/docs/prod/folder...75lbc176a.html

Package is SOIC.

They're both TI, so why the different numbering (1176 vs 176)? What does
65/75 prefix indicate? And regarding the other markings on the failed IC:
does HT mean Hi-Temp?

A few too many discrepancies in my mind to just swap it in just yet.

Thanks,

The LBC devices appear to be upgrades to their respective ALS
versions. They specify lower power and improved ESD.

The 65 versions appear to have a wider operating temp range (-40C to
125C, -40C to 85C) than the 75 versions (0 to 70C).

The datasheets are he

http://focus.ti.com/lit/ds/symlink/sn65lbc176a.pdf
http://focus.ti.com/lit/ds/symlink/sn75lbc176a.pdf (same as previous)
http://focus.ti.com/lit/ds/symlink/sn65als1176.pdf

All devices have an SN75176 "footprint".

- Franc Zabkar
--
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