REV. C

–4–

AD7249

PIN FUNCTION DESCRIPTION (DIP & SOIC PIN NUMBERS)

Pin

Mnemonic

Description

REFOUT

Voltage Reference Output. The internal 5 V analog reference is provided at this pin. To operate the

part using its internal reference, REFOUT should be connected to REFIN.

REFIN

Voltage Reference Input. It is internally buffered before being applied to both DACs. The nominal

reference voltage for specified operation of the AD7249 is 5 V.

AGND for the +10 V range and to REFIN for the –5 V to +5 V range.

Analog Output Voltage of DAC B. This is the buffer amplifier output voltage. Three different output

voltage ranges can be chosen: 0 V to +5 V, 0 V to +10 V and –5 V to +5 V.

AGND

Analog Ground. Ground reference for all analog circuitry.

CLR

unipolar ranges and the twos complement bipolar range and to –REFIN in the offset binary bipolar

range.

BIN/COMP

Logic Input. This input selects the data format to be either binary or twos complement. In both uni-

polar ranges natural binary format is selected by connecting this input to a Logic “0”. In the bipolar

configuration offset binary format is selected with a Logic “0” while a Logic “1” selects twos complement.

DGND

Digital Ground. Ground reference for all digital circuitry.

SDIN

Serial Data In, Logic Input. The 16-bit serial data word is applied to this input.

10

LDAC

Load DAC, Logic Input. Updates both DAC outputs. The DAC outputs are updated on the falling

edge of this signal or alternatively if this line is permanently low, an automatic update mode is se-

lected whereby both DACs are updated on the 16th falling SCLK pulse.

11

SCLK

Serial Clock, Logic Input. Data is clocked into the input register on each falling SCLK edge.

12

SYNC

Data Synchronization Pulse, Logic Input. Taking this input low initializes the internal logic in readi-

ness for a new data word.

13

Positive Power Supply.

14

Analog Output Voltage of DAC A. This is the buffer amplifier output voltage. Three different output

voltage ranges can be chosen: 0 V to +5 V, 0 V to +10 V and –5 V to +5 V.

15

Negative Power Supply (used for the output amplifier only) may be connected to 0 V for single sup-

ply operation or –12 V to –15 V for dual supplies.

16

AGND for the +10 V range and to REFIN for the –5 V to +5 V range.

PIN CONFIGURATIONS

(DIP and SOIC)

TOP VIEW

(Not to Scale)

16

15

14

13

12

11

10

9

1

2

3

4

5

6

7

8

REFOUT

AD7249

REFIN

AGND

SYNC

CLR

SCLK

BIN/COMP

LDAC

DGND

SDIN

ORDERING GUIDE

Temperature

Relative

Package

Model

Range

Accuracy

Option

AD7249AN

–40

°C to +85°C

±1 LSB

N-16

AD7249BN

–40

°C to +85°C

±1/2 LSB

N-16

AD7249AR

–40

°C to +85°C

±1 LSB

R-16

AD7249BR

–40

°C to +85°C

±1/2 LSB

R-16

AD7249SQ

1

–55

°C to +125°C

±1 LSB

Q-16

NOTE

data sheet.