Flash erasing times

[Richard Hutchinson]

Does age affect the erase time for Flash memory ?. I have a batch of
identical chips, some erase is 6 seconds other take 15 (datasheet specifies
10).

 

[Eric Smith]

"Richard Hutchinson" <richard.hutchinson@dsl.pipex.com> writes:

Does age affect the erase time for Flash memory ?. I have a batch of
identical chips, some erase is 6 seconds other take 15 (datasheet specifies
10).

I wouldn't expect much effect as a strict function of age, but I would
expect that as the part is subjected to many erase cycles, they would
start to take longer.

I think manufacturing variation between lots could account for quite a
bit of variation.

But I'm not an expert on this stuff.

 

[Rich Webb]

On Tue, 5 Feb 2008 19:08:54 -0000, "Richard Hutchinson"
<richard.hutchinson@dsl.pipex.com> wrote:

Does age affect the erase time for Flash memory ?. I have a batch of
identical chips, some erase is 6 seconds other take 15 (datasheet specifies
10).

Be careful with datasheets. Is 10 sec specified as guaranteed maximum
erase time at a specific Vdd and temperature or is 10 the nominal?

--
Rich Webb Norfolk, VA

 

[Richard Hutchinson]

is 10 the nominal?

Yes


I'll take it the one's with erase times of 15+ seconds are probably coming
to the end of their life.

 

[Rich Webb]

On Wed, 6 Feb 2008 15:21:56 -0000, "Richard Hutchinson"
<richard.hutchinson@dsl.pipex.com> wrote:

is 10 the nominal?

Yes


I'll take it the one's with erase times of 15+ seconds are probably coming
to the end of their life.

Not necessarily. If they don't spec a guaranteed maximum erase time,
there's probably a reason. A time of 15 secs could very well be within
the process variation for a part right off the manufacturing floor.

--
Rich Webb Norfolk, VA