Low Power, 12-Bit CMO S D ACs

D AC349

D ata Converter Line

FEATURES

• 12-bits binary or 3-decades BDC

• Low power: 300mW

• Commercial, industrial and M IL-STD-883 models

• 5 pin selectable output ranges

DESCRIP TION

The DA C349 Series are versatile, low power 12-bit D/A

converters that are intended for fixed reference

applications. These units combine a novel CM OS

switching technique with a precision, ultra-stable

thin-film ladder to achieve accurate conversion with

low power drain; improved reliability and near-

instantaneous warmup are major advantages of

reduced power consumption. A ll models include an

internal precision reference and a gain-selectable

output amplifier.

The DA C349 Series offers a choice of either 12-bit

binary coding (-12 models) or 3 decade BCD coding

(-3D models).

By external pin jumpering, the binary models can be

connected for unipolar output ranges of 0 to

–5V or 0 to –10V and for offset binary coded bipolar

outputs of ±2.5V , ±5V and ±10V . For ratiometric

applications, the units operate from an external fixed

DC reference of –10V ± 10% .

Both binary and BCD models are available in

commercial/industrial and M IL-STD-883 Rev. C, Level B

versions. The DA C349B is specified over a

temperature range of –55ºC to +125ºC. Both versions

operate –55ºCto +125ºC.

FUNCTIONAL DIAGRAM

GND

12

GND

11

+15V

10

– 15V

10

BIPOLA R

OFFSET

10

20V

RA NGE

4

10V

RA NGE

3

SUM M ING

JUNCTION

3

* FOR BCD (-3D M ODELs),

R1 + R2 = 80k

GA IN A DJ

REF OUT

JUM PER

REF IN

6

8

7

13

12

14

11

15

10

16

9

17

8

18

19

20 21

22 23

24

7

6

5

4

3

2

1

1

2

4

8

10

20 40

80 100 200 400 800

BINA RY

BIT

BCD

(- 12 M ODELS)

(- 3D M ODELS)

(M SB)

(LSB)

- 10V DC

REF

PRECISION RESISTOR LA DDER

A ND SW ITCHES

R1

50k

R2

50k

100k

–

+

OUTPUT

1

165Cedar Hill Street,Marlborough,MA01752 Tel:508.485.6350 Fax: 508.485.5168

www.SpectrumMicrowave.com