>
>Hi Dudes
>I am having a problem erasing my Pic 14000 widowed device.
>I have two of them and both doesn't want to be erased by the
>UV light.I have programmed both of them at most ten times,if that much.
>Now the MPLAB software just tells me the device is not clean, and I
>have been placing them under the light for about 15mins or longer.
>It doesn't get damaged that quiqly ,even when you leve it in the eraser
>too long??Or does it ?

I've had windowed EPROMS damaged by two mechanisms:-

1.      Putting them in the programmer when still quite warm

and

2.      Static electricity


Note on above:-

1.      This is easy to control by obvious methods
2.      This is a very misunderstood random element that needs proper control,
        by the correct equipment (such as that by 3M).

        The effects (or recurrence) of static damage is never to be
underestimated,
        if  in doubt send you devices back to microchip and they should be able
        to tell pretty quickly if the device failed due to static.

General point on Static:-

If you are developing applications in any control environment, put yourself in
the passenger seat of a jet - such as the air bus 'fly by wire' airliner. Not
only can some control systems result in death if damaged, they take up a great
deal of time to pin down.

Static damage need not be catastrophic - At The Time it Occurs. Devices specs
can be compromised and the device can then fail catastrophically ANY time
later !

Some years ago HP investigated this quite thoroughly - anybody happen to know
if these reports are available via internet ? ?


Rgds

Mike

Some say there is no magic but, all things begin with thought then it becomes
academic, then some poor slob works out a practical way to implement all that
theory, this is called Engineering - for most people another form of magic.
                                                                       Massen