Cirrus Logic CS3308 - Manual

Copyright
© Cirrus Logic, Inc. 2006
(All Rights Reserved)
http://www.cirrus.com
8-Channel Analog Volume Control
Features
 Complete Analog Volume Control
– 8 Independently Controllable Channels
– 3 Configurable Master Volume and Muting
Controls
 Wide Adjustable Volume Range
– -96 dB to +22 dB in ¼ dB Steps
 Low Distortion & Noise
– -112 dB THD+N
– 123 dB Dynamic Range
 Noise-Free Level Transitions
– Zero-Crossing Detection with
Programmable Time-Out
 Low Channel-to-Channel Crosstalk
– 120 dB Inter-Channel Isolation
 Comprehensive Serial Control Port
– Supports I²C ® and SPI TM Communication
– Independent Control of up to 128 Devices
on a Shared 2-Wire I²C or 3-Wire SPI
Control Bus
– Supports Individual and Grouped Control of
all CS3308 Devices on the I²C or SPI
Control Bus
 Standard Power Supply Voltages
– ±5 V Analog Supply
– +3.3 V Digital Supply
Description
The CS3308 is an 8-channel digitally controlled analog
volume control designed specifically for high-end audio
systems. It features a comprehensive I²C/SPI serial
control port for easy device and volume configuration.
The CS3308 includes arrays of well-matched resistors
and complementary low-noise active output stages. A
total adjustable range of 118 dB, in ¼ dB steps, is
spread evenly over 96 dB of attenuation and 22 dB of
gain.
The CS3308 implements configurable zero-crossing
detection to provide glitch-free volume-level changes.
The I²C/SPI control interface provides for easy system
integration of up to 128 CS3308 devices over a single 2-
wire I²C or 3-wire SPI bus, allowing many channels of
volume control with minimal system controller I/O re-
quirements. Devices may be controlled on an individual
and grouped basis, simplifying simultaneous configura-
tion of a group of channels across multiple devices,
while allowing discrete control over all channels on an
individual basis.
The device operates from ±5 V analog supplies and has
an input/output voltage range of ±3.65 V. The digital
control interface operates at +3.3 V.
The CS3308 is available in a 48-pin LQFP package in
Commercial grade (-10° to 70° C). The CS3308 Cus-
tomer Demonstration board is also available for device
evaluation. Refer to
“Ordering Information” on page 44
for complete details.
±5 V
+3.3 V
8-Channel
Analog
Outputs
I²C/SPI
Serial
Control
8
+
_
Zero Crossing
Detector
I²C / SPI
Control
Port
8-Channel
Analog
Inputs
8
DECEMBER '06
DS702F1
CS3308