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IMP1

Application Information

Operation – Power Monitor

The DS1810 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 detected, the RESET signal is asserted. On power-up,

RESET is kept active (LOW) 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.

Output Conditions

remains above 1.2V. The RESET output on the IMP1810 uses a

push-pull drive stage that can maintain a valid output below 1.2V.

from the reset pin (RESET) to Ground (see Figure 1). This config-

approaching 0V. During both power up and down, this configu-

ration will draw current when RESET is in the high state. A value

of 100k

Ω should be adequate to maintain a valid condition.

IMP1810

Microprocessor

RESET

100k

RESET

1810_06.eps

Figure 2. Timing Diagram: Power-Up

Figure 3. Timing Diagram: Power-Down

RESET

1810_07.eps

RESET

1810_08.eps