DUAL RAIL-TO-RAIL CMOS OPERATIONAL AMPLIFIER

ALD2704A/ALD2704B

ALD2704

GENERAL DESCRIPTION

The ALD2704 is a dual monolithic operational amplifier with MOSFET

input that has rail-to-rail input and output voltage ranges. The input

voltage range and output voltage range are very close to the positive and

negative power supply voltages.

Typically the input voltage can be

beyond positive power supply voltage V+ or the negative power supply

voltage V- by up to 300mV. The output voltage swings to within 60mV of

either positive or negative power supply voltages at rated load.

With high impedance load,

the output voltage of the ALD2704 ap-

proaches within 1mV of the power supply rails. This device is designed

as an alternative to the popular J-FET input operational amplifier in

applications where lower operating voltages, such as 9V battery or

±3.25V

to

±6V power supplies are being used. The ALD2704 offers high slew rate

of 5V/

µs. It is designed and manufactured with Advanced Linear Devices'

standard enhanced ACMOS silicon gate CMOS process, and it offers low

unit cost and exceptional reliability.

The rail-to-rail input and output feature of the ALD2704 expands signal

voltage range for a given operating supply voltage and allows numerous

analog serial stages to be implemented without losing operating voltage

margin. The output stage is designed to drive up to 10mA into 400pF

capacitive and 1.5K

Ω resistive loads at unity gain and up to 4000pF at a

gain of 5. Short circuit protection to either ground or the power supply rails

is at approximately 15mA clamp current. Due to complementary output

stage design, the output can source and sink 10mA into a load with

symmetrical drive and is ideally suited for applications where push-pull

voltage drive is desired.

For each of the operational amplifier, the offset voltage is trimmed on-chip

to eliminate the need for external nulling in many applications.

For

precision applications, the output is designed to settle to 0.1% in 2

µs. In

large signal buffer applications, the operational amplifier can function as

an ultrahigh input impedance voltage follower /buffer that allows input and

output voltage swings from positive to negative supply voltages. This

feature is intended to greatly simplify systems design and eliminate higher

voltage power supplies in many applications.

FEATURES

• Rail-to-rail input and output voltage ranges

• Symmetrical push-pull output drives

• Output settles to 2mV of supply rails

• 5.0V/

µs slew rate

• High capacitive load capability -- up to 4000pF

• No frequency compensation required -- unity

gain stable

• Extremely low input bias currents -- <1.0pA

typical (20pA max.)

• Ideal for high source impedance applications

• High voltage gain -- typically 100V/mV

• Output short circuit protected

• Unity gain bandwidth of 2.1MHz

APPLICATIONS

• Voltage amplifier

• Voltage follower/buffer

• Charge integrator

• Photodiode amplifier

• Data acquisition systems

• High performance portable instruments

• Signal conditioning circuits

• Low leakage amplifiers

• Active filters

• Sample/Hold amplifier

• Picoammeter

• Current to voltage converter

• Coaxial cable driver

• Capacitive sensor amplifier

• Piezoelectric transducer amplifier

PIN CONFIGURATION

1

2

3

4

8

7

6

5

TOP VIEW

DA, PA, SA PACKAGE

V+

V -

Operating Temperature Range*

-55

°C to +125°C0°C to +70°C0°C to +70°C

8-Pin

8-Pin

8-Pin

CERDIP

Small Outline

Plastic Dip

Package

Package (SOIC)

Package

ALD2704A DA

ALD2704A SA

ALD2704A PA

ALD2704B DA

ALD2704B SA

ALD2704B PA

ALD2704 DA

ALD2704 SA

ALD2704 PA

ORDERING INFORMATION

* Contact factory for industrial temperature range

© 1998 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, California 94089 -1706 Tel: (408) 747-1155 Fax: (408) 747-1286 http://www.aldinc.com