IMP1817
Application Information
Operation – Power Monitor
The IMP1817 detects out-of-tolerance power supply conditions. It
resets a processor during power-up, power-down and issues a
reset to the system processor when the monitored power supply
voltage is below the reset threshold. When an out-of-tolerance VCC
voltage is detected, the RESET signal is asserted. On power-up,
RESET is kept active (HIGH) for approximately 150ms 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)
IMP1817
Microprocessor
VIN
tRPU
RESET
RESET
VOL
RESET
1817_07.eps
1815_07.eps
Figure 2. Timing Diagram: Power-Up
Figure 1. RESET Valid to 0V VCC
tF
VCC
VCCTP (MAX)
VCCTP
VCCTP (MIN)
tRPD
VOH
RESET Slews with VCC
RESET
1817_08.eps
Figure 3. Timing Diagram: Power-Down
408-432-9100/www.impweb.com
© 1999 IMP, Inc.
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A1PROS [ A1 PROS CO., LTD. ]
