WM2633

Byte-wide Parallel Input, 12-bit Voltage Output DAC

with Internal Reference

Production Data, July 1999, Rev 1.0

WOLFSON MICROELECTRONICS LTD

Lutton Court, Bernard Terrace, Edinburgh, EH8 9NX, UK

Tel: +44 (0) 131 667 9386

Fax: +44 (0) 131 667 5176

Email: sales@wolfson.co.uk

http://www.wolfson.co.uk

Production Data contain final specifications

current on publication date. Supply of

products conforms to Wolfson

Microelectronics’ Terms and conditions.

masterrev1.0.doc 07/15/99 3:52

1999 Wolfson Microelectronics Ltd

.

FEATURES

• 12-bit voltage output DAC

• Dual supply 2.7V to 5.5V operation

• DNL ±0.3 LSBs, INL ±1.2 LSBs

• Internal programmable voltage reference

• Programmable settling time

• 8-bit micro controller compatible interface

• Power down mode (10nA)

APPLICATIONS

• Battery powered test instruments

• Digital offset and gain adjustment

• Battery operated/remote industrial controls

• Machine and motion control devices

• Wireless telephone and communication systems

• Speech synthesis

• Arbitrary waveform generation

ORDERING INFORMATION

DEVICE

TEMP. RANGE

PACKAGE

WM2633CDT

0

° to 70°C

20-pin TSSOP

WM2633IDT

-40

° to 85°C

20-pin TSSOP

DESCRIPTION

The WM2633 is a 12-bit voltage output, resistor string, digital-

to-analogue converter. A hardware controlled power down mode

is provided that reduces current consumption to 10nA. The

WM2633 features an internal programmable voltage reference

simplifying overall system design. A reference voltage may also

be supplied externally.

The device has an 8-bit microcontroller compatible parallel

interface. The eight data LSBs, the four data MSBs, and the five

control bits are written using three different addresses.

Excellent performance is delivered with a typical DNL of 0.3

LSBs and a typical INL of 1.2 LSBs. The output stage is

buffered by a x2 gain near rail-to-rail amplifier, which features a

Class A output stage (slow mode, Class AB). The settling time

of the DAC is software or pin programmable to allow the

designer to optimise speed versus power dissipation.

The

device

is

available

in

a

20-pin

TSSOP

package.

Commercial

temperature

(0°

to

70°C)

and

Industrial

temperature (-40° to 85°C) variants are supported.

BLOCK DIAGRAM

TYPICAL PERFORMANCE

(13) OUT

D[0-7]

(19,20, 1-6)

3-BIT

CONTROL

LATCH

REF(12)

POWER-ON

RESET

NWE (17)

(14)

GND

REFERENCE

INPUT BUFFER

WM2633

DAC

OUTPUT

BUFFER

NCS (18)

A[0-1] (8, 7)

4-BIT DAC

MSW

HOLDING

LATCH

8-BIT DAC

LSW

HOLDING

LATCH

X1

POWERDOWN/

SPEED

CONTROL

X2

(16)

NLDAC

PARALLEL

INTERFACE

AND

CONTROL

LOGIC

SPD (9)

NPD (15)

12-BIT DAC

LATCH

DVDD

(10)

AVDD

(11)

2-BIT

REFERENCE

SELECT

LATCH

1.024V/2.048V

SELECTABLE

REFERENCE

X1

REFERENCE

OUTPUT BUFFER

WITH OUPUT

ENABLE

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

0

512

1024

1536

2048

2559

3071

3583

4095

DIGITAL CODE