Differences between TMS2732 and Intel 2732A

I was recently reading some schematics that required me to take into the differences between TMS2716 and 2716A. The differences I found I believe to be so that the TMS2716 could e pin compatiable with the

2708. When I went to look for the data sheet on the TMS2732 all I could find were the data sheets for the 2732A. Does anybody remember if similar differences exist between TMS2732 and the 2732A so that it can be to some degree backwards compatiable with 2708 and TMS2716?

Sincerely, Derek

Reply to
Derek Simmons
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Google for TMS2532 They had a different pinout to the Intel 2732

Thats a lot more murky: the TMS2716 was based on 2708 technology and had several supplyvoltages. The later TMS2516 was compatible to the Intel 2716

MfG JRD

Reply to
Rafael Deliano

TMS2732 datasheet can be found here:

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Reply to
JW

Thanks, but the datasheet at

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is for the forward thinking TMS2732A with a single power source while the one I'm wondering about is for the TMS2732 (or maybe the TMS2532) that was backwards compatiable with TMS2708 that required 3 power supplies.

Reply to
Derek Simmons

Note that the pinout is Intel but the programming voltage 21V vs the original 25V.

There weren´t that many variants. Text is in german but pinouts should be obvious:

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MfG JRD

Reply to
Rafael Deliano

Any socket that could support both the 2708/TMS2716 and any later parts would have needed a bunch of jumpers, properly configured, to not fry one of the newer parts with a negative supply voltage.

I dug back into my old databooks and tried to remember the world of dueling EPROMs circa 1979. Both Intel's 2732 and TI's were 5 volt single supply parts. Both originally were 25 volt programming, but that dropped to 21 volts for the 2732A.

They were running out of pins for all the address lines (and went to 28 pins for the 64k bit parts). TI's 2532 had a dedicated Vpp pin so it only had room for one enable pin, which combined Chip Enable with Output Enable. Intel shared the Vpp with Output Enable, and had a seperate Chip Enable, so it could use any address setup time on the bus before the output enable (read) signal was provided, and run faster depending on the bus cycle timing. So Intel won. And TI ended up cloning the 2732A.

It was all kind of academic, because 4k bytes was still too small for anything but a toy program and everybody jumped to the 64k (8k byte) parts as soon as possible.

I've got the Motorola MCM2532 version datasheet up on my ftp directory, , if you need the pinout. (Been there since 2004, hope it still works). A quick and sloppy skim of both Motorola and TI sheets looks that they're the same, except for minor variations in the programming spec.

Motorola did make the MCM68764 and MCM68766 24 pin 64k bit parts, (basically, a doubled 2532) which were useful a few years back when a bunch of Mostek 64k bit masked ROMS, with the same pinout, started dying of bitrot and a bunch of the early era micro controlled test equipment lost their minds. I've got those datasheets up, too.

Mark Zenier snipped-for-privacy@eskimo.com Googleproofaddress(account:mzenier provider:eskimo domain:com)

Reply to
Mark Zenier

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