Re: [uCsimm] Are the uCsimm I/O pins 5V Tolerant?

From: Tom Walsh (tom@mytoys.com)
Date: Sat Feb 05 2000 - 01:56:25 EST


Sam Saprunoff wrote:

> Hello everyone!
>
> Well, I received the info from Motorola via a good chap at FAI (Arden
> Wagner)... Now we (I) have a definitive answer to this question.
>
> Cheers,
>
> Sam
>
> >Hello Sam:
> >
> >Here you go.
>
> >Arden,
>
> >The MC68EZ328 pins are not 5 Volt tolerant for continuous operation. The
> >specification of -0.3 V to 7.0 V is for transient inputs not continuous.
> >Appropriate operation of the part is not guaranteed under 5 Volt continuous
> >inputs to the pins. If needed level converters may be implemented.
> >Regards,
> >Adrian Pineda

So what is it they are saying? "Yes" you can use +5v input levels, but "No" if you
continue to do this then the part may not function as documented? For example the
DRAM controller suddenly stops operating?

I just love Motorola, they make everything so simple, for the automotive
industry... First the docs say the pins are tolerant then the FAE (Field
Application Engineer) says they are not! I am just happy that my ethernet device is
functional at a 3.3v supply, GEEZ!

TomW

>
>

--
Tom Walsh - WN3L - Embedded Systems Consultant - tom over_at mytoys(.)com
'www.mytoys.com', 'www.openhardware.net', 'www.cyberiansoftware.com'
"Windows? No thanks, I have work to do..."

This message resent by the ucsimm@uclinux.com list server http://www.uClinux.com/



This archive was generated by hypermail 2b30 : Sun Apr 07 2002 - 00:01:34 EST