> Could you share the gory details of your PIC brownout
Did you say CHEAP? AN522 details a brownout circuit that just uses
a PNP transistor and three resistors. It is not as accurate as the
ones using zeners, or the dedicated microcontroller reset chips, but
it can be built for $0.05 US (if you are building a million of them)
If you don't have a paper copy of the Embedded Control Handbook,
then download AN522 from http://www.microchip.com.
This brownout protection circuit is simple but it works well. I
have never had any trouble with it.
If you are really interested in TESTING for brownouts I have a
conplete plan for a brownout test circuit on my web page. It is
designed around a simple 12C508 running a 120 volt relay. The relay
interrupts power to the appliance under test at varying intervals
from a few tens of milliseconds to ten seconds. This simulates the
range of brownouts commonly seen in mains power systems. Any
appliance which can stand this treatment for 24 hours without going
mad passes my test for brownout resistance.
-- Lawrence Lile
"Nyquist was an optimist."
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