ETC MP022

SIMPLECIRCUIT™
Low Cost Iron Safety Timer
Author:
FIGURE 1:
Jason Wolfson
Lipider Corp.
Duxbury ,MA
USA
email: [email protected]
FLOWCHART
Power-up
Turn on Triac
INTRODUCTION
Zero Detect?
Clothes irons and curling irons are high powered appliances that can start house fires. Many times after leaving for work you forget if you shut-off or unplug the
dangerous appliances. This timer will allow the appliance to have power for only a fixed amount of time
(without motion/use). Then it will shut-off power. A reset
switch will restart the appliance.
No
Yes
Decrement time
Time-out?
No
Yes
Turn off
Check switch?
No
Yes
FIGURE 2:
SCHEMATIC
Vcc
GP2/TOCKI
Load
GP3
GP1
PIC12C508
Microchip Technology Incorporated, has been granted a nonexclusive, worldwide license to reproduce, publish and distribute all submitted materials, in
either original or edited form. The author has affirmed that this work is an original, unpublished work and that he/she owns all rights to such work. All
property rights, such as patents, copyrights and trademarks remain with the author.
 1997 Microchip Technology Inc.
DS40160A/3_022-page 3-15
SimpleCircuit™
DS40160A/3_022-page 3-16
 1997 Microchip Technology Inc.