FUNCTIONAL BLOCK DIAGRAM

BURIED ZENER REF

COMP-

ARATOR

ANALOG

IN

DB9

HIGH

BYTE

10-BIT

CURRENT

OUTPUT

DAC

V+

V–

DIGITAL

COMMON

CONVERT

INT

CLOCK

10-BIT

SAR

DB8

DB7

DB6

DB5

DB4

DB3

DB2

DB1

DB0

HBE

LBE

MSB

LSB

LOW

BYTE

ANALOG

COMMON

BIPOLAR

OFFSET

CONTROL

DATA

READY

AD573

5k

REV. A

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

10-Bit A/D Converter

AD573*

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

Tel: 617/329-4700

Fax: 617/326-8703

FEATURES

Complete 10-Bit A/D Converter with Reference, Clock

and Comparator

Full 8- or 16-Bit Microprocessor Bus Interface

Fast Successive Approximation Conversion—20

s typ

No Missing Codes Over Temperature

Operates on +5 V and –12 V to –15 V Supplies

Low Cost Monolithic Construction

PRODUCT DESCRIPTION

The AD573 is a complete 10-bit successive approximation

analog-to-digital converter consisting of a DAC, voltage refer-

ence, clock, comparator, successive approximation register

(SAR) and three state output buffers—all fabricated on a single

chip. No external components are required to perform a full

accuracy 10-bit conversion in 20

µs.

The AD573 incorporates advanced integrated circuit design and

processing technologies. The successive approximation function

is implemented with I

ming of the high stability SiCr thin-film resistor ladder network

insures high accuracy, which is maintained with a temperature

compensated subsurface Zener reference.

Operating on supplies of +5 V and –12 V to –15 V, the AD573

will accept analog inputs of 0 V to +10 V or –5 V to +5 V. The

trailing edge of a positive pulse on the CONVERT line initiates

the 20

µs conversion cycle. DATA READY indicates completion

of the conversion. HIGH BYTE ENABLE (HBE) and LOW

BYTE ENABLE

(LBE) control the 8-bit and 2-bit three state

output buffers.

The AD573 is available in two versions for the 0

°C to +70°C

temperature range, the AD573J and AD573K. The AD573S

guarantees

±1 LSB relative accuracy and no missing codes from

–55

°C to +125°C.

Three package configurations are offered. All versions are offered

in a 20-pin hermetically sealed ceramic DIP. The AD573J and

AD573K are also available in a 20-pin plastic DIP or 20-pin

leaded chip carrier.

*Protected by U.S. Patent Nos. 3,940,760; 4,213,806; 4,136,349; 4,400,689;

and 4,400,690.

PRODUCT HIGHLIGHTS

l. The AD573 is a complete 10-bit A/D converter. No external

components are required to perform a conversion.

2. The AD573 interfaces to many popular microprocessors

without external buffers or peripheral interface adapters. The

10 bits of output data can be read as a 10-bit word or as 8-

and 2-bit words.

3. The device offers true 10-bit accuracy and exhibits no miss-

ing codes over its entire operating temperature range.

4. The AD573 adapts to either unipolar (0 V to +10 V) or

bipolar (–5 V to +5 V) analog inputs by simply grounding or

opening a single pin.

5. Performance is guaranteed with +5 V and –12 V or –15 V

supplies.

6. The AD573 is available in a version compliant with MIL-STD-

883. Refer to the Analog Devices Military Products Data-

book or current /883B data sheet for detailed specifications.