>
> I've forgotten how long to cook 'em for.
>
> I can't find a time specified in either the 12c5xx data sheet or in the
> 12c5xx programming specification.
>
> Eraser is an Ango LA6R, 2540 angstroms, 25VA rating. Exposure mat about
> the size of a credit card and a bit.
>
> I know this has been discussed last year. ;-}
James. You erase them until they're erased.
Start with 16 minutes. If they erase then 1/2 the amount of time. Continue
to do so until they won't erase anymore. Go back to the proceeding time
and you may want to add a minute or two for good margin.
So if it erases fine at 8 minutes and not a 4 then 10 minutes is probably
a good target.
Trust me. Unless you bake them for weeks, you're not going to do any real
damage. They're still EPROMs and they pretty much follow EPROM erasure
specifications that has the total UV absorpion on the order of months.
>
> I've forgotten how long to cook 'em for.
>
> I can't find a time specified in either the 12c5xx data sheet or in the
> 12c5xx programming specification.
>
> Eraser is an Ango LA6R, 2540 angstroms, 25VA rating. Exposure mat about
> the size of a credit card and a bit.
>
> I know this has been discussed last year. ;-}
James. You erase them until they're erased.
Start with 16 minutes. If they erase then 1/2 the amount of time. Continue
to do so until they won't erase anymore. Go back to the proceeding time
and you may want to add a minute or two for good margin.
So if it erases fine at 8 minutes and not a 4 then 10 minutes is probably
a good target.
Trust me. Unless you bake them for weeks, you're not going to do any real
damage. They're still EPROMs and they pretty much follow EPROM erasure
specifications that has the total UV absorpion on the order of months.
BAJ
---------------------------------------------
I have to disagree to the above statement.
I forgot 5 PIC16C73A's under the UV light overnight.
The next day I could only program 2 of them.
<x-flowed>At 07:13 AM 12/14/99 -0500, BAJ wrote:
>Start with 16 minutes. If they erase then 1/2 the amount of time. Continue
>to do so until they won't erase anymore. Go back to the proceeding time
>and you may want to add a minute or two for good margin.
>
>So if it erases fine at 8 minutes and not a 4 then 10 minutes is probably
>a good target.
>
>Trust me. Unless you bake them for weeks, you're not going to do any real
>damage. They're still EPROMs and they pretty much follow EPROM erasure
>specifications that has the total UV absorpion on the order of months.
Actually, 3-5 minutes seems to be enough. I'd start with 5 minutes and do a
blank check. If it's ok, then the erase is ok. If there are unchanged bits,
do it another 5 minutes.
================================================================
Robert A. LaBudde, PhD, PAS, Dpl. ACAFS e-mail: .....ralKILLspam@spam@lcfltd.com
Least Cost Formulations, Ltd. URL: http://lcfltd.com/
824 Timberlake Drive Tel: 757-467-0954
Virginia Beach, VA 23464-3239 Fax: 757-467-2947
"Vere scire est per causae scire"
================================================================
It's also been my experience that the more program/erase cycles you put on a
device, the longer it can take to erase, until finally the device won't
erase at all.
us.netrek.org http://quozl.us.netrek.org/
