We cannot bless an OKI part number as an acceptable replacement for a
Toshiba or TI chip. We do not have access to the parts in question or the
specifications of the OKI parts. Based on the part number it sounds like
you want to upgrade the card with 2.0 MB of RAM to a total of 2.5 MB of
RAM.
The best answer is for you to contact Marshall's Electronics telemarketing
department at 800-800-2968 and ask to purchase, via credit card, the proper
parts. There is a $50.00 minimum purchase requirement.
These are two parts they have in stock:
1) For 0.5 MB upgrade: Use TI part number TMS44C256-10SD @ $8.20 each
(need 4 per card)
2) For 2.0 MB upgrade: Use TI part number TMS44000-12SD @ 27.50 each (need
4 per card). You may also used Toshiba part number TC514400AZ-80.
The Marshall's telemarketing staff is quite helpful on equivalent ZIP chip
modules which have the bit density (256K x 4 or 1024K x 4) and the proper
speed (120ns minimum). The parts are rare but a large semiconductor
distributor has them.
Article Change History:
17 Nov 1993 - Updated to the proper chip speed.