General Description

The MAX975/MAX977 single/dual comparators feature

three different operating modes, and are optimized for

+3V and +5V single-supply applications. The operating

modes are as follows: high speed, high speed with

auto-standby, and low power. Propagation delay is 28ns

in high-speed mode, while supply current is only 250

µA.

Supply current is reduced to 3µA in low-power mode.

The auto-standby feature allows the comparator to

automatically change from low-power mode to high-

speed mode upon receipt of an input signal. In the

absence of an input signal, the comparator reverts

back to low-power mode after an adjustable timeout

period. The timeout period for the MAX975 to enter

standby is set by a single capacitor. The dual MAX977

features independently adjustable timeout periods for

each comparator using separate capacitors.

The MAX975/MAX977’s inputs have a common-mode

input voltage range extends rail to rail. The outputs are

capable of rail-to-rail operation without external pull-up

circuitry, making these devices ideal for interface with

CMOS/TTL logic. All inputs and outputs can tolerate a

continuous short-circuit fault condition to either rail. The

comparator’s internal hysteresis in high-speed mode

ensures clean output switching, even with slow-moving

input signals.

The single MAX975 is available in 8-pin SO and 8-pin

µMAX packages, while the dual MAX977 is available in

14-pin SO and 16-pin QSOP packages.

________________________Applications

Battery-Powered Systems

RF ID Tags

Keyless Entry

Threshold Detectors/Discriminators

3V Systems

IR Receivers

Digital-Line Receivers

____________________________Features

♦ Three Operating Modes:

High Speed

High Speed with Auto-Standby

Low Power

♦ 28ns Propagation Delay (high-speed mode)

♦ 5µA Max Supply Current in Low-Power/

Auto-Standby Modes

♦ +3V/+5V Single-Supply Operation

♦ Rail-to-Rail Outputs

♦ Ground-Sensing Input

♦ Internal Hysteresis (high-speed mode)

♦ Adjustable Timeout Period

♦ µMAX Package (MAX975)

QSOP-16 Package (MAX977)

Single/Dual, +3V/+5V Dual-Speed

Comparators with Auto-Standby

________________________________________________________________

Maxim Integrated Products

1

Functional Diagram

19-1141; Rev 1; 11/98

PART

MAX975ESA

MAX975EUA

MAX977ESD

-40°C to +85°C

-40°C to +85°C

-40°C to +85°C

TEMP. RANGE

PIN-PACKAGE

8 SO

8 µMAX

14 SO

Ordering Information

Pin Configurations appear at end of data sheet.

MAX977EEE

-40°C to +85°C

16 QSOP

MAX975

IN+

LP

OUT

GND

STO

HIGH SPEED

LOW POWER

ENABLE

IN-

STAT

TIMING

CIRCUIT

ENABLE

TRANSITION

MONITOR

For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.

For small orders, phone 1-800-835-8769.