REV. A

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a

LOGDAC

CMOS Logarithmic D/A Converter

AD7118*

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

Tel: 617/329-4700

Fax: 617/326-8703

GENERAL DESCRIPTION

The LOGDAC

verter which attenuates an analog input signal over the range

0 to –85.5 dB in 1.5 dB steps. The analog output is determined

by a six-bit attenuation code applied to the digital inputs.

Operating frequency range of the device is from dc to several

hundred kHz.

The device is manufactured using an advanced monolithic

silicon gate thin-film on CMOS process and is packaged in a

14-pin dual-in-line package.

ORDERING INFORMATION

Specified

Temperature

Accuracy

Package

Model

Range

Range

Option

1

AD7118KN

0

°C to +70°C

0 to 42 dB

N-16

AD7118LN

0

°C to +70°C

0 to 48 dB

N-16

AD7118BQ

–25

°C to +85°C

0 to 42 dB

Q-16

AD7118CQ

–25

°C to +85°C

0 to 48 dB

Q-16

AD7118TQ

2

–55

°C to +125°C

0 to 42 dB

Q-16

AD7118UQ

2

–55

°C to +125°C

0 to 48 dB

Q-16

NOTES

*Protected by U.S. Patent No. 4521,764.

LOGDAC is a registered trademark of Analog Devices, Inc.

FEATURES

Dynamic Range 85.5 dB

Resolution 1.5 dB

Full

25 V Input Range Multiplying DAC

Full Military Temperature Range –55 C to +125 C

Low Distortion

Low Power Consumption

Latch Proof Operation (Schottky Diodes Not Required)

Single 5 V to 15 V Supply

APPLICATIONS

Digitally Controlled AGC Systems

Audio Attenuators

Wide Dynamic Range A/D Converters

Sonar Systems

Function Generators

FUNCTIONAL DIAGRAM

PIN CONFIGURATION