WM2630

Octal 12-bit, Serial Input, Voltage Output DAC

with Internal Reference

Production Data, February 2001, Rev 1.1

WOLFSON MICROELECTRONICS LTD

Bernard Terrace, Edinburgh, EH8 9NX, UK

Tel: +44 (0) 131 667 9386

Fax: +44 (0) 131 667 5176

Email: sales@wolfson.co.uk

www.wolfsonmicro.co.uk

Production Data datasheets contain final

specifications current on publication date.

Supply of products conforms to Wolfson

Microelectronics’ Terms and Conditions.

©2001 Wolfson Microelectronics Ltd

.

FEATURES

•

Eight 12-bit DACs in one package

•

Dual supply 2.7V to 5.5V operation

•

DNL

±0.5 LSBs, INL ±2.0 LSBs typ.

•

Programmable settling time / power

(1.0

µs typ. in fast mode)

•

Internal programmable Voltage Reference

•

Microcontroller compatible Serial Interface

•

Power Down Mode ( < 0.1

µA)

•

Monotonic over Temperature

•

Data Output for Daisy Chaining

APPLICATIONS

•

Battery powered test instruments

•

Digital offset and gain adjustment

•

Battery operated / remote industrial controls

•

Programmable Loop Controllers

•

CNC Machine Tools

•

Machine and motion control devices

•

Wireless telephone and communication systems

•

Robotics

ORDERING INFORMATION

DEVICE

TEMP. RANGE

PACKAGE

WM2630CDT

0

° to 70°C

20-pin TSSOP

WM2630IDT

-40

° to 85°C

20-pin TSSOP

DESCRIPTION

The WM2630 is an octal, 12-bit, resistor string digital-to-

analogue converter. The eight individual DACs contained in the

IC can be switched in pairs between fast and slow (low power)

operation modes, or powered down, under software control.

Alternatively, the whole device can be powered down, reducing

current consumption to less than 0.1

µA.

The DAC outputs are buffered by a rail-to-rail amplifier with a

gain of two, which is configurable as Class A (fast mode) or

Class AB (for low-power mode).

The WM2630 has been designed to interface directly to

industry standard microprocessors and DSPs, and can

operate on two separate analogue and digital power supplies. It

is programmed with a 16-bit serial word comprising 4 address

bits and up to 12 DAC or control register data bits. All eight

DACs can be simultaneously forced to a preset value using a

preset input pin.

A daisy-chain data output makes it possible to control several

of Wolfson’s octal DACs from the same interface, without

increasing the number of control lines.

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

LATCH

POWER/SPEED

CONTROL

RESISTOR

STRING

(12) OUT A

DAC A

DIN (2)

SCLK (3)

FS (4)

PREB (5)

1.024V / 2.048V

SELECTABLE

REFERENCE

DOUT (19)

REF

(16)

DACs B, C, D, E, F, G, H

as DAC A

(6-9, 13-15)

OUT B to H

REF

SERIAL

INTERFACE

AND

CONTROL

LOGIC

MODE (17)

AVDD

(11)

DVDD

(20)

AGND

(10)

DGND

(1)

LOADB

(18)

-1

-0.75

-0.5

-0.25

0

0.25

0.5

0.75

1

0

512

1024

1536

2048

2560

3072

3584

4096

DIGITAL CODE