General Description

The MAX6457–MAX6460 high supply voltage, low-power

voltage monitors operate over a 4V to 28V supply voltage

range. Each device includes a precision bandgap refer-

ence, one or two low-offset voltage comparators, internal

threshold hysteresis, power-good or reset timeout

options, and one or two high-voltage open-drain outputs.

Two external resistors (three for window detection) set the

trip threshold voltages.

The MAX6457 is a single voltage monitor for undervoltage

or overvoltage detection. A logic-based clear input either

latches the output for overvoltage applications or allows

the device to operate in transparent mode. The MAX6458

includes two comparators (one overvoltage and one

undervoltage) for window detection and a single output to

indicate if the monitored input is within an adjustable volt-

age window. The MAX6459 includes dual overvoltage/

undervoltage comparators with two independent com-

parator outputs. Use the MAX6459 as a window com-

parator with separate undervoltage and overvoltage

outputs or as two independent, single voltage monitors.

The MAX6460 includes a single comparator and an inter-

nal reference, and can also accept an external reference.

The inverting and noninverting inputs of the comparator

are externally accessible to support positive or negative

voltage monitors and to configure the device for active-

high or active-low output logic.

The MAX6457/MAX6458 offer fixed timing options as a

voltage detector with a 50µs typical delay or as a reset cir-

cuit with a 90ms minimum reset timeout delay. The moni-

tored input must be above the adjusted trip threshold (or

within the adjusted voltage window for the MAX6458) for

the selected timeout period before the output changes

state. The MAX6459/MAX6460 offer only a fixed 50µs

timeout period. Internal threshold hysteresis options (0.5%,

5%, and 8.3% for the MAX6457/MAX6458/MAX6459, and

0.5% for the MAX6460) reduce output chatter in noise-

sensitive applications. Each device is available in a small

SOT23 package and specified over the extended temper-

ature range of -40°C to +125°C.

Applications

Undervoltage Monitoring/Shutdown

Overvoltage Monitoring/Protection

Window Voltage Detection Circuitry

Multicell Battery-Stack Powered Equipment

Notebooks, eBooks

Automotive

Industrial

Telecom

Networking

Features

o Wide Supply Voltage Range, 4V to 28V

o Internal 2.25V ±2.5% Reference

o Low Current (3.5µA, typ at 12V)

o Open-Drain n-Channel Output (28V Compliant)

o Internal Threshold Hysteresis Options

(0.5%, 5%, 8.3%)

o Two IN-to-OUT Timeout Period Options

(50µs, 150ms)

o Internal Undervoltage Lockout

o Immune to Short Voltage Transients

o Small SOT23 Packages

o Few External Components

o Fully Specified from -40°C to +125°C

High-Voltage, Low-Current Voltage Monitors in

SOT Packages

Ordering Information

5-CELL

Li+

BATTERY

STACK

BATTERY

CHARGER

DC-DC

CONVERTER

LOAD

R1

R2

SHDN

+21V (NOMINAL)

GND

CLEAR

IN+

OUT

MAX6457

IN

OUT

Typical Operating Circuit

19-2534; Rev 5; 7/12

1

For pricing, delivery, and ordering information, please contact Maxim Direct

at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Pin Configurations appear at end of data sheet.

PART

TEMP RANGE

PIN-PACKAGE

MAX6457UKD_ _-T

-40°C to +125°C

5 SOT23

MAX6458UKD_ _-T

-40°C to +125°C

5 SOT23

MAX6459UT_-T

-40°C to +125°C

6 SOT23

MAX6460UT-T

-40°C to +125°C

6 SOT23

Note: The MAX6457/MAX6458/MAX6459 are available with

factory-trimmed internal hysteresis options. The MAX6457 and

MAX6458 offer two fixed timing options. Select the desired hys-

teresis and timing options using Table 1 or the Selector Guide at

the end of the data sheet, and enter the corresponding letters

and numbers in the part number by replacing “_ _” or “_”. These

devices are offered in tape-and-reel only and must be ordered in

2500-piece increments.

Devices are available in both leaded and lead(Pb)-free/RoHS-

compliant packaging. Specify lead(Pb)-free by replacing “-T”

with “+T” when ordering.