IMP1233D
Application Information
Operation – Power Monitor
The IMP1233D detects out-of-tolerance power supply conditions.
It resets a processor during power-up and issues a reset to the sys-
tem processor when the monitored power supply voltage is below
the reset threshold (power-down). When an out-of-tolerance VCC
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.
tR
VCCTP (MAX)
VCCTP
VCCTP (MIN)
VCC
tRPU
VOH
RESET
1233D_06.eps
Figure 1. Timing Diagram: Power-Up
tF
VCC
VCCTP (MAX)
VCCTP
VCCTP (MIN)
tRPD
RESET
VOL
1233D_07.eps
Figure 2. Timing Diagram: Power-Down
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© 1999 IMP, Inc.
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