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General Description

The MIC2774 is a dual power supply supervisor that

provides undervoltage monitoring, manual reset

capability, and power-on reset generation in a compact

5-pin SOT-23 package. Features include two

undervoltage detectors, one fixed and one adjustable,

and a choice of reset outputs. One undervoltage

detector compares VDD against a fixed threshold. Ten

factory-programmed thresholds are available. The

second, user-adjustable input is compared against a

300 mV reference. This low reference voltage allows

for the monitoring of voltages lower than those

supported by previous supervisor ICs.

The reset outputs are asserted at power-on and at any

time either voltage drops below the programmed

threshold voltage and remains asserted for 140 ms

(min.) after they subsequently rise back above the

threshold boundaries. Manual reset functionality can

be provided by a switch connected between ground

and the /MR input. A wide choice of voltage thresholds

provides for a variety of supply voltages and

tolerances. Hysteresis is included to prevent chattering

due to noise. Typical supply current is a low 3.5 ¦ÌA.

Features

? Monitors Two Independent Power Supplies for

Undervoltage Conditions

? One Fixed and One User-Adjustable Input

? Choice of Ten Factory-Programmed Thresholds

? Adjustable Input can Monitor Supplies as Low as

0.3V

? Generates 140 ms (min.) Power-On Reset Pulse

? Manual Reset Input

? Choice of Active-High, Active-Low, or Open-Drain

Active-Low Reset Outputs

? Inputs May be Pulled Above VDD (7V abs. max.)

? /RST Output Valid Down to 1.2V

? Ultra-Low Supply Current, 3.5 ¦ÌA Typical

? Rejects Brief Input Transients

? IttyBitty 5-pin SOT-23 Package

? Pin-Compatible upgrade for MAX6306/09/12

Applications

? Monitoring Processor ASIC or FPGA Core and

I/O Voltages

? PDAs, Handheld PCs

? Embedded Controllers

? Telecommunications Systems

? Power Supplies

? Wireless/Cellular Systems

? Networking Hardware