AVR-Chat

At 12:51 AM 6/24/2006, you wrote:
>Hi,
>
>     Does anyone know, almost for sure, that the external res and cap are not
>needed anymore ?? I know they cost very little but with TQFP parts the size
>matters. :-)
>
>Best regards,
>Alexandre Guimaraes

  I don't know for sure, But thinking along the same lines as you seem to 
be... I left the external reset resistor & cap off my last design.

  Everything seems to work fine, including ISP. But I did notice that when 
I brushed my finger on the ISP connector and at the same time touched the 
tab of a HV switching FET I'd get spontaneous resets.
  This is a bit extreme, but I think the answer is that in a normal noise 
environment you can leave the parts out of the design. In a high noise 
situation put them in, or better yet disable the reset pin entirely after 
development is done (proper use of BOD is probably advised.)

Sorry for only having anecdotal evidence.

-carl


----------------------------------------------
Henry Carl Ott   N2RVQ
tech@si.rr.com