MIC833

Micrel

MIC833

4

January 2000

Functional Description

The MIC833 monitors a voltage and detects when it is below

or above two independently programmed levels.

Voltage Low Output

The output (OUT) is an active-high, open-drain output which

sinks current when the MIC833 detects a low input voltage at

its LTH input. This condition is latched until the HTH input is

presented with a voltage higher than the internal V

REF

(+1.24V).

Block Diagram

GND

+1.5V to +5.5V

OUT

1.24V

Bandgap

Reference

Low-Voltage

Detect

High-Voltage

Detect

R

S

Q

Q

LTH

HTH

MIC833

VDD

3

1

2

4

5

Trip Points

Input voltage is monitored by the comparators via a voltage

divider network. The divided voltage is compared to an

internal reference voltage. When the voltage at the LTH input

pin drops below the internal reference voltage, the output

pulls low. Because of the voltage divider, the voltage at HTH

is assured to be below the reference voltage.