[SI-LIST] : overshoot

Jeff Miller-FJM039 (Jeff_Miller-FJM039@email.mot.com)
Wed, 26 Aug 1998 23:53:35 -0500

Ok, I'm a rookie, so go easy on me. I am having trouble with a signal
on a board we just built. The signal is a CE for a memory device.
During certain conditions, there is a short duration pulse on this line.
Two things are happening that causes me concern.

1) When it pulses high, it tops out at about 3.6 - 3.8V (operating
voltage of board is 3.3V)
2) When the signals is once again driven low, there is ringing.

My assumptions is that reflections are causing the ringing, however I'm
have no clue about the additional 300 mV on the high part of pulse.

Any ideas on either of the above?

Thanks in advance for any help.

Jeff Miller
Electrical Engineer
Motorola LinkWorks Division
(817)-245-4833 (voice)
(817)-245-4279 (fax)
(800)-759-8352 (#2454833) (pager)

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