WM2618

Dual 12-bit Serial Input Voltage Output DAC

Production Data, October 2000, Rev 1.1

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 datasheets contain final

specifications current on publication date.

Supply of products conforms to Wolfson

Microelectronics’ Terms and Conditions.

2000 Wolfson Microelectronics Ltd

.

FEATURES

• Two 12-bit voltage output DACs

• Single supply from 2.7V to 5.5V supply operation

• DNL ±0.5 LSB, INL ±1.9

• Low power consumption

- 3mW typical in slow mode

- 8mW typical in fast mode

• TMS320, (Q)SPI, and Microwire compatible

serial interface

• Programmable settling time 4µs or 12µs typical

APPLICATIONS

•

Battery powered test instruments

•

Digital offset and gain adjustment

•

Battery operated/remote industrial controls

•

Machine and motion control devices

•

Cellular telephones

•

Wireless telephone and communication systems

•

Speech synthesis

•

Arbitrary waveform generation

ORDERING INFORMATION

DEVICE

TEMP. RANGE

PACKAGE

WM2618CD

0° to 70°C

8-pin SOIC

WM2618ID

-40° to 85°C

8-pin SOIC

DESCRIPTION

The WM2618 is a dual 12-bit voltage output, resistor string,

digital-to-analogue

converter.

A

power-on-reset

function

ensures repeatable start-up conditions.

The device has been designed to interface efficiently to industry

standard microprocessors and DSPs, including the TMS320

family. The WM2618 is programmed with a 16-bit serial word.

The WM2618 has a simple-to-use single 2.7V to 5.5V supply.

The digital inputs feature Schmitt triggers for high noise

immunity.

The number of clocks from the falling edge of NCS are counted

automatically. The device is then updated and disabled from

accepting further data inputs.

Excellent performance is delivered with a typical DNL of ±0.5

LSBs. The settling time of the DAC is programmable to allow

the designer to optimise speed versus power dissipation.

The device is available in an 8-pin SOIC package ideal for

space-critical applications. Commercial temperature (0° to

70°C) and Industrial temperature (-40° to 85°C) variants are

supported.

BLOCK DIAGRAM

TYPICAL PERFORMANCE

(7) OUTB

(4) OUTA

12-BIT

DAC B

HOLDING

LATCH

12-BIT

DAC A

LATCH

REFIN(6)

POWER-ON

RESET

DIN (1)

SCLK (2)

NCS (3)

(5)

AGND

VDD

(8)

POWERDOWN/

SPEED

CONTROL

12-BIT

DAC B

CONTROL

LATCH

DAC

OUTPUT

BUFFER

2-BIT

CONTROL

LATCH

X1

X1

X2

X2

DAC

OUTPUT

BUFFER

REFERENCE

INPUT BUFFER

REFERENCE

INPUT BUFFER

WM2618

16-BIT

SHIFT

REGISTER

AND

CONTROL

LOGIC

data

-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