FUNCTIONAL BLOCK DIAGRAM

REV. A

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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

16/18-Bit Self-Calibrating

Serial/Byte DACPORT

AD760

© 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

±0.2 LSB (±0.00031%) Typ Peak DNL and INL

±0.5 LSB (±0.00076%) Typ Unipolar Offset, Bipolar Zero

17-Bit Monotonicity Guaranteed

18-Bit Resolution (in Serial Mode)

Complete 16/18-Bit D/A Function

On-Chip Output Amplifier

On-Chip Buried Zener Voltage Reference

Microprocessor Compatible

Serial or Byte Input

Double Buffered Latches

Asynchronous Clear Function

Serial Output Pin Facilitates Daisy Chaining

Pin Strappable Unipolar or Bipolar Output

Low THD+N: 0.005%

MUX Output Control on Power-Up and Supply Glitches

+10V

REF

10k

SPAN/

BIP

OFF

9.95k

LDAC

REF IN

REF OUT

HBE

SER

CLR

10k

AD760

UNI/

BIP CLR

OR

LBE

AGND

OR

DB0

DB2

DB7

CS

MSB/

LSB

OR

DB1

12

18/16

SERIAL

OR

24

23

15

27

28

22

25

17

18

20

21

19

MAIN DAC

16

26

RAM

CALIBRATION SEQUENCER

CALOK

DGND

CAL

1

2

3

5

6

4

14

16/18-BIT

INPUT REGISTER

13

7

CALIBRATION DAC

16/18-BIT DAC LATCH

Typical Integral Nonlinearity

DACPORT is a registered trademark of Analog Devices, Inc.

0.75

0.25

0

–0.25

–0.75

0

16384

32768

49152

65535

INPUT CODE – Decimal

MUX output in a predetermined state by means of a digital and

analog power supply detection circuit. This is particularly use-

ful for robotic and industrial control applications.

The AD760 is available in a 28-pin, 600 mil cerdip package.

The AQ version is specified from –40°C to +85°C.

PRODUCT DESCRIPTION

The AD760 is a complete 16/18-bit self-calibrating monolithic

DAC (DACPORT®) with onboard voltage reference, double

buffered latches and output amplifier. It is manufactured on

Analog Devices’ BiMOS II process. This process allows the fab-

rication of low power CMOS logic functions on the same chip

as high precision bipolar linear circuitry.

Self-calibration is initiated by simply pulsing the CAL pin low.

The CALOK pin indicates when calibration has been success-

to send the output to the bottom of the output range during

calibration.

Data can be loaded into the AD760 as straight binary, serial

data or as two 8-bit bytes. In serial mode, 16-bit or 18-bit data

can be used and the serial mode input format is pin selectable,

to be MSB or LSB first. This is made possible by three digital

input pins which have dual functions (Pins 12, 13, and 14). In

byte mode the user can similarly define whether the high byte or

user to daisy chain several AD760s by shifting the data through

the input latch into the next DAC thus minimizing the number

of control lines required in a multiple DAC application. The

double buffered latch structure eliminates data skew errors and

provides for simultaneous updating of DACs in a multi-DAC

system.

The asynchronous CLR function can be configured to clear the

output to minus full-scale or midscale depending on the state of

Pin 17 when CLR is strobed. The AD760 also powers up with the