REV. 0

Information furnished by Analog Devices is believed to be accurate and

reliable. However, no responsibility is assumed by Analog Devices for its

use, nor for any infringements of patents or other rights of third parties

which may result from its use. No license is granted by implication or

otherwise under any patent or patent rights of Analog Devices.

a

Dual, 16 MHz, Rail-to-Rail

FET Input Amplifier

AD823

© Analog Devices, Inc., 1995

One Technology Way, P.O. Box 9106, Norwood. MA 02062-9106, U.S.A.

Tel: 617/329-4700

Fax: 617/326-8703

FEATURES

Single Supply Operation

Output Swings Rail to Rail

Input Voltage Range Extends Below Ground

Single Supply Capability from +3 V to +36 V

High Load Drive

Capacitive Load Drive of 500 pF, G = +1

Output Current of 15 mA, 0.5 V from Supplies

Excellent AC Performance on 2.6 mA/Amplifier

–3 dB Bandwidth of 16 MHz, G = +1

350 ns Settling Time to 0.01% (2 V Step)

Slew Rate of 22 V/ s

Good DC Performance

800

V Max Input Offset Voltage

2

V/ C Offset Voltage Drift

25 pA Max Input Bias Current

Low Distortion

–108 dBc Worst Harmonic @ 20 kHz

Low Noise

16 nV/

√Hz @ 10 kHz

No Phase Inversion with Inputs to the Supply Rails

APPLICATIONS

Battery Powered Precision Instrumentation

Photodiode Preamps

Active Filters

12- to 16-Bit Data Acquisition Systems

Medical Instrumentation

CONNECTION DIAGRAM

8-Pin Plastic Mini-DIP

and

8-Lead SOIC

1

2

3

4

8

7

6

5

AD823

OUT1

+IN2

–IN2

OUT2

–IN1

+IN1

PRODUCT DESCRIPTION

The AD823 is a dual precision, 16 MHz, JFET input op amp

that can operate from a single supply of +3.0 V to +36 V, or

dual supplies of

±1.5 V to ±18 V. It has true single supply

capability with an input voltage range extending below ground

in single supply mode. Output voltage swing extends to within

≤ 100 µA providing outstanding out-

put dynamic range.

Offset voltage of 800

µV max, offset voltage drift of 2 µV/°C,

input bias currents below 25 pA and low input voltage noise

provide dc precision with source impedances up to a Gigohm.

16 MHz, –3 dB bandwidth, –108 dB THD @ 20 kHz and

22 V/

µs slew rate are provided with a low supply current of

2.6 mA per amplifier. The AD823 drives up to 500 pF of direct

capacitive load as a follower, and provides an output current of

15 mA, 0.5 V from the supply rails. This allows the amplifier to

handle a wide range of load conditions.

This combination of ac and dc performance, plus the outstand-

ing load drive capability results in an exceptionally versatile am-

plifier for applications such as A/D drivers, high-speed active

filters, and other low voltage, high dynamic range systems.

The AD823 is available over the industrial temperature range of

–40

°C to +85°C and is offered in both 8-pin plastic DIP and

SOIC packages.

3V

GND

200µs

500mV

FREQUENCY – Hz

–8

1k

–6

–7

2

1

10k

100k

1M

G = +1

–5

–4

–3

–2

–1

0

10M

Figure 2. Small Signal Bandwidth, G = +1