ASM161, ASM162

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2

Figure 1. Typical Operating Circuit

Figure 2. Block Diagram

Table 1. PIN DESCRIPTION

Pin #

Pin Name

Function

ASM161

ASM162

1

1

GND

Ground.

2

−

RESET

An external pull−up resistor is needed.

−

2

RESET

3

3

MR

Manual reset input. A negative going edge transition on MR asserts reset. Reset

remains asserted for one reset time−out period (800 ms min). This active−LOW input

has an internal pull−up resistor. It can be driven from a TTL or CMOS logic line or

shorted to ground with a switch. Leave open if unused.

4

4

Power supply input voltage.

Detailed Description

The reset function ensures the microprocessor is properly

reset and powers up into a known condition after a power

failure.

Reset Timing

A reset is generated whenever the supply voltage is below

and is guaranteed to be no more than 2 seconds. The rest

signal remains active as long as the monitored supply

voltage is below the internal threshold voltage.

The ASM161 has an open−drain, active LOW RESET

down to 1.1 V). The ASM161 uses an external pull−up

resistor. Output leakage current is under 1

mA. A high

resistance value can be used to minimize current drain.

The ASM162 generates an active−HIGH RESET output.