> >>Hi,
> >>
> >>I bought a few JW devices (x54,x56,x57) about two years ago.  These
> >>devices erased in about 4 minutes under my eraser.  Recently I
> >>bought another x57 and this chip takes 12+ minutes to erase under the
> >>same lamp!  Is the part suspect or have Microchip made their devices a
> >>bit harder to erase in the last two years?
> >
> >Look in the window and compare die sizes.
>
> >Andy
>
> Exactly! If the die is smaller, allow more erase time.
>

The die is actually smaller, but (this might be a stupid question) why
would a smaller die take longer to erase?  If the floating gates are
smaller, then less charge will be on them and then it would take less
time to remove it...?

Niki
steenkmp@firga.sun.ac.za