IMP1233M
Application Information
Operation – Power Monitor
The IMP1233M detects out-of-tolerance power supply conditions.
It resets a processor during power-up and issues a reset to the
system processor when the monitored power supply voltage
is below the reset threshold (power-down). When an out-of-
tolerance V
CC
voltage is detected, the RESET signal is asserted. On
power-up, RESET is kept active (LOW) for approximately 350ms
after the power supply voltage has reached the selected tolerance.
This allows the power supply and microprocessor to stabilize
before RESET is released.
t
R
V
HTL
V
LTL
V
CCTP
V
CC
t
RPU
V
OH
RESET
1233M_05.eps
Figure 1. Timing Diagram: Power-Up
t
F
V
CC
V
HTL
V
CCTP
V
LTL
t
RPD
RESET
V
OL
1233M_06.eps
Figure 2. Timing Diagram: Power-Down
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