© Semiconductor Components Industries, LLC, 2011

August, 2011 − Rev. 3

1

Publication Order Number:

ASM1834/D

ASM1834, ASM1834A,

ASM1834D

Dual 5 V and 3.3 V mP

Power Supply Supervisor

with Manual Reset

Description

The ASM1834 supervisors simultaneously monitor both 3.3 V and

5 V power sources and generate reset signals when either supply is out

of tolerance. When an out−of−tolerance condition is detected, the

output−reset signal of the affected supply becomes active and resets

the system microprocessor/microcontroller. On power−up and after

the supply voltage returns to an in−tolerance condition, the reset signal

remains active for approximately 350 ms. This allows the power

supply and system microprocessor to stabilize.

Tolerance levels are independently selectable for both supplies.

Tolerance options are 5% and 10% for the 5 V supply and 10% and

20% for the 3.3 V supply.

The ASM1834 and ASM1834D have push−pull reset output stages.

The ASM1834A reset outputs are open drain devices that can both be

connected to either 5 V or 3.3 V supply. The ASM1834 and

ASM1834A have active LOW reset outputs. The ASM1834D has

active HIGH reset outputs.

All devices can generate reset signals through an internally

debounced pushbutton reset input that affects both reset outputs.

All devices operate over the extended industrial temperature range.

Devices are available in 8−pin DIP, surface mount 8−pin SO and 8−Pin

MicroSO packages. Die are also available.

Features

ASM1834, ASM1834D

Eliminates External Pull−up Resistors

Active LOW (ASM1834), HIGH (ASM1834D)

ASM1834A

Active LOW

5 V or 3.3 V

and Comparator

DIP Packages

Applications

http://onsemi.com

PIN CONFIGURATION

See detailed ordering and shipping information in the package

dimensions section on page 11 of this data sheet.

ORDERING INFORMATION

PDIP−8

NO SUFFIX

CASE 646AA

SOIC−8

S SUFFIX

CASE 751BD

5V RESET*

5V TOL

GND

3.3V RESET*

3.3V TOL

PBRST

ASM1834

ASM1834A

ASM1834D

1

MICRO−8

U SUFFIX

CASE 846AA

*AS1834D reset outputs are active HIGH

(5V RESET and 3.3V RESET) Outputs are

open−drain for AS1834A.

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