TC32M_06 Datasheet, PDF (6/12 Pages) Microchip Technology – ECONOMONITOR- 3-Pin System Supervisor with Power Supply Monitor and Watchdog

TC32M
3.4 External Override Reset Control
A built-in debounce circuit allows a push-button switch
(PB) or other electronic signal to be wire-ORed to this
pin as an external Reset override control. The external
Reset is required to be an active low signal. Internally,
this input is timed to provide a minimum Reset pulse
width of 500 msec. Reference Figure .
t
PB Closed
PB Open
RS
V_IL
FIGURE 3-2:
V_IH
t_RST
RS Pulled Low By Push-
Button Reset
5V
V_DD
V_RST
t_RPD
RS
V_IL
t_RST
V_IH
FIGURE 3-3: Power-Up/Down Reset Timing
3.5 Supply Monitor Noise Sensitivity
The TC32M is optimized for fast response to negative-
going changes in V_DD. Systems with an inordinate
amount of electrical noise on V_DD (such as systems
using relays), may require a 0.01 μF bypass capacitor
to reduce detection sensitivity. This capacitor should be
installed as close to the TC32M as possible to keep the
capacitor lead length short.
5V
R1, 10 kΩ
R2,10 kΩ
Microcontroller
PO.1
RS
TC32M
Reset
Reset
R1, 10 kΩ
RS
TC32M
R2, 10 kΩ ^Decoder
Reset
Microprocessor
Address
Reset
Microcontroller Example
Microprocessor Example
FIGURE 3-4:
TC32M Hardware Connections (R1, R2 Chosen To Meet V_STH, V_STL)
DS21402C-page 6
© 2006 Microchip Technology Inc.