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WM8816

Stereo Digital Volume Control

WOLFSON MICROELECTRONICS plc

www.wolfsonmicro.com

Product Preview, October 2004, Rev 1.5

Copyright

2004 Wolfson Microelectronics plc

DESCRIPTION

The WM8816 is a highly linear stereo volume control for

audio systems. The design is based on resistor chains with

external op-amps, which provides flexibility for the supply

voltage, signal swing, noise floor and cost optimisation. The

gain of each channel can be independently programmed

from -111.5dB to +15.5dB through a digital serial control

interface.

Audible clicks on gain changes are eliminated by changing

gains only when a zero crossing has been detected in the

signal. The device also features peak level detection, which

can be used for Automatic Gain Control. The WM8816

operates from a single +5V supply and accepts signal input

levels up to ±18V.

The WM8816 is available in a 16-pin SOIC package. It is

guaranteed over a temperature range of -20

° to +60°C.

FEATURES

•

Gain range from -111.5dB to +15.5dB

•

0.5dB Gain step size

•

Total Harmonic Distortion 0.001% (100dB) typical

•

Crosstalk -110dB typical

•

Input signals up to ±18V

•

Zero Detection for Gain Changes

•

Hardware and Software Mute

•

Power On/Off Transient Suppression

APPLICATIONS

•

Audio Amplifiers

•

Consumer Audio / Entertainment Systems

•

Mixing Desks

•

Audio Recording Equipment

BLOCK DIAGRAM

Zero

Crossing

Detector

Zero

Crossing

Detector

Peak

Level

Detector

Peak

Level

Detector

CSB

MUTEB

DATA

CCLK

LGND

LIN

DAC

LFO

LMO

RIN

RGND

RFO

RMO

AVDD

AGND

DVDD

DGND

+

-

+

-

LEFT OUT

RIGHT OUT

External Opamps

Control

WM8816