Problem burning Texas Instrument eproms.

[bust3dstr8]

I pulled about 20 TMS27C040 from a parts board and they all erased fine.

The problem is they all program about dozen or so bytes and then fail.

 

The TI datsheet says VPP 13V and pulse 100µs, that's what my programmer

defaults to when I select the chip.

 

 

Is it possible that all the chips are just tired or more likely that the programmer

isn't configured properly to write these?

[matthew180]

I have had some chips (can't remember if they were specifically TI EPROMs) that would not program when I selected the correct part from my programmer's selection list. However, trying a different manufacturer for the same size EPROM, in some cases, would successfully program the EPROM. To me that is more a failure of the software than the EPROM, but it could also be because the parts are old. Then again, I'm also using a piece of crap parallel port programmer that only works on XP systems with a CPU slower than 1GHz...

[+batari]

Not sure what you're using, but I've found that parallel port programmers need a real parallel port from a desktop PC. They don't work well with laptops or with any sort of add-on card or device.

 

Also, some require Windows 98 or older. Even if the software appears to run in later versions, often it doesn't work right.

[bust3dstr8]

I just tossed this whole batch in the garbage. My buddy tried some in his high end programmer and they all failed for him too.

His guess was that Incredible Technologies are idiots and programed them at too high VPP and killed the chips.