Re: LED & Resistor befuddlement

From: CBFalconer (cbfalconer_at_yahoo.com)
Date: 06/03/04 

Date: Thu, 03 Jun 2004 11:44:14 GMT

Peter Jakacki wrote:
>
... snip ...
>
> I would skip the pulldown resistor altogether and simply drive the
> output low for a few cycles then switch it back to an input.
> The CMOS inputs have more than enough capacitance and a low enough
> leakage to hold the charge from the last driven state.

Bad idea. You just don't leave CMOS input lines open. They can
drift to a state where both input transistors are on, and just
drawing excess current without limit. 

-- 
fix (vb.): 1. to paper over, obscure, hide from public view; 2.
to work around, in a way that produces unintended consequences
that are worse than the original problem.  Usage: "Windows ME
fixes many of the shortcomings of Windows 98 SE". - Hutchison