It's a tough break when that happens.

It's exactly why Microchip have successfull with the OTP's. They can work
out cheaper (more cost effective as Microchip would say) than going to ROM
when things like that happen. If you talk to your Microchip rep, you will
probably find that they would rather screw down the price on your OTP's in
volume rether than going mask ROM.

Motorola on the other hand, would rather go ROM than OTP.... Horses for
courses.

Temic on the 8051 types expect screw up's - they give you one free turn -
and you use it!

Rgds...

...Andy
At 16:08 17/02/99 -0500, you wrote:
>At 08:25 PM 2/17/99 +0000, Andy Stephenson wrote:
>>OTP is PROM, which is an EPROM with no window.
>>
>>The pattern 'blown' into a ROM is done with metalisation layers during the
>>final stages of production, which means that you have to commit to a lot of
>>parts.
>
>They're cheap, as long as you're <SURE> your code is not going to change.
>We went OTP for a while and then mask, and still ended up with a bug in one
>product. It was discovered about 8 weeks after we submitted our code for a
>12 week process, and had committed to 5000 chips.
>
>Fortunately, it wasn't a huge bug.
>