TC32M Datasheet, PDF (3/4 Pages) TelCom Semiconductor, Inc – ECONOMONITOR - 3-PIN SYSTEM SUPERVISOR WITH POWER SUPPLY MONITOR AND WATCHDOG

ECONOMONITOR™ – 3-PIN SYSTEM SUPERVISOR
WITH POWER SUPPLY MONITOR AND WATCHDOG
1
TC32M
RS
V_STH (MIN)
V_STL (MAX)
V_STL (MIN)
t_ST
t_TD
Note: t_TD is the maximum elapsed time between strobes which
will keep the watchdog timer from forcing RS LOW.
(A STROBE is defined as a high-to-low transition from V_STH to V_STL).
Figure 1. Watchdog Strobe
V_DD
V_RST
t_RPD
RS
V_IL
t_RST
V_IH
Figure 3. Power Up / Down Reset Timing
2
3
4
PB CLOSED PB OPEN
RS
VIH
VIL
t_RST
Figure 2. RS Pulled Low by Push-button Reset
PIN DESCRIPTION
Pin No.
Symbol
1
GND
2
V_DD
3
RS
4
V_DD
Description
Ground.
The +5V power supply input.
RESET/STROBE (Bidirectional). The open drain goes active if:
1. V_DD falls below 4.5V nominal.
2. If pulled low by an external electronic signal or switch closure.
3. If the watchdog is not strobed within the minimum watchdog timeout period.
4. During power-up and power-down.
In the input mode, RS connects to a voltage level shift network (typically a resistor divider
to V_DD.) The watchdog timer is reset when processor causes a voltage level ≤ V_STL to be
applied to RS.
The +5V power supply input. (SOT-223 only).
5
6
7
8
TELCOM SEMICONDUCTOR, INC.
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