SSM2160 Datasheet, PDF (1/16 Pages) Analog Devices – 6- and 4-Channel, Serial Input Master/Balance Volume Controls

a
6- and 4-Channel, Serial Input
Master/Balance Volume Controls
SSM2160/SSM2161
FEATURES
Clickless Digitally Controlled Level Adjustment
SSM2160: Six Channels
SSM2161: Four Channels
7-Bit Master Control Gives 128 Levels of Attenuation
5-Bit Channel Controls Give 32 Levels of Gain
Master/Channel Step Size Set by External Resistors
100 dB Dynamic Range
Automatic Power On Mute
Excellent Audio Characteristics:
0.01% THD+N
0.001% IMD (SMPTE)
–90 dBu Noise Floor
–80 dB Channel Separation
90 dB SNR
Single and Dual Supply Operation
APPLICATIONS
Home Theater Receivers
Surround Sound Decoders
Circle Surround* and AC-3* Decoders
DSP Soundfield Processors
HDTV and Surround TV Audio Systems
Automotive Surround Sound Systems
Multiple Input Mixer Consoles and Amplifiers
GENERAL DESCRIPTION
The SSM2160 and SSM2161 allow digital control of volume of
six and four audio channels, respectively, with a master level
control and individual channel controls. Low distortion VCAs
(Voltage Controlled Amplifiers) are used in the signal path. By
using controlled rate-of-change drive to the VCAs, the “click-
ing” associated with switched resistive networks is eliminated in
the Master control. Each channel is controlled by a dedicated
5-bit DAC providing 32 levels of gain. A master 7-bit DAC
feeds every control port giving 128 levels of attenuation. Step
sizes are nominally 1 dB and can be changed by external
resistors. Channel balance is maintained over the entire master
control range. Upon power-up, all outputs are automatically
muted. A three- or four-wire serial data bus enables interfacing
with most popular microcontrollers. Windows* software and an
evaluation board for controlling the SSM2160 are available.
The SSM2160 can be operated from single supplies of +10 V to
+20 V or dual supplies from ± 5 V to ± 10 V. The SSM2161 can
be operated from single supplies of +8.5 V to +20 V (for
automotive applications) or dual supplies from ± 4.25 V to
± 10 V. An on-chip reference provides the correct analog
common voltage for single supply applications. Both models
come in P-DIP and SO packages. See the Ordering Guide for
more details.
REV. 0
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
FUNCTIONAL BLOCK DIAGRAM
V+
V–
V_REF
POWER
SUPPLY AND
REFERENCE
GENERATOR
5-BIT
CHANNEL
∑
DAC
5-BIT
CHANNEL
∑
DAC
5-BIT
CHANNEL
∑
DAC
5-BIT
CHANNEL
∑
DAC
5-BIT
CHANNEL
∑
DAC
5-BIT
CHANNEL
∑
DAC
7-BIT
MASTER
DAC
CLK
DATA
LD
WRITE
SHIFT REGISTER
AND
ADDRESS
DECODER
VCA
CH1 IN
CH1 OUT
VCA
CH2 IN
CH2 OUT
VCA
CH3 IN
CH3 OUT
VCA
CH4 IN
CH4 OUT
VCA
CH5 IN
CH5 OUT
VCA
CH6 IN
CH6 OUT
STEP SIZE
ADJUST
CH SET
MSTR SET
MSTR OUT
*Circle Surround is a registered trademark of Rocktron Corporation.
AC-3 is a registered trademark of Dolby Labs, Inc. Windows is a regis-
tered trademark of Microsoft Corp.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] World Wide Web Site: http://www.analog.com
Fax: [phone]
© Analog Devices, Inc., 1996