Audio
Audio/Voice DSP
CX20805
High-Performance Low-Power Digital Audio Signal Processor
The CX20805 is a 32-bit dual core Digital
Signal Processor (DSP), designed using
Conexant Audio Processing Engine
(CAPE) cores. The CX20805 audio
processor offers customers
programmability and flexibility in their
designs by providing a cost- effective
architecture which needs high
performance and low power. CX20805 is
the first high performance, low-power
audio DSP in the audio market that offers
over 800 MIPS
(1)
to support
computationally intensive audio
processing algorithms with large on-chip
memory 520KB SRAM/352KB ROM and
capable of supporting all major high
sampling rates through various audio
interfaces to external SoCs and Analog
Mixed Signal chipsets.
The device features support for up to four
digital microphone inputs, support for dual
bi-directional I
2
S, PCM, S/PDIF transmit
and receive with independent sampling
rates, and a range of digital input/output
channel selections for flexible routing and
mixing. Different audio sampling rates
ranging from 8 kHz to 96 kHz are
generated directly from the master clock
without the need for external PLL. The
device can be controlled and configured
by both read and write capability through
I
2
C and Serial Peripheral Interface (SPI).
The USB interface supports both High
speed and Full speed, and is USB2.0
Audio Class compliant for both data and
control. An integrated on-chip 128-bit
AES decoding engine is present for
copyright protection and rendering full-
rate, lossless Blu-ray media content.
There are six timers/counters on chip
which can be used for different
application based requirements.
The device also has a Conexant Audio
Bus (CAB) interface which has been
specially developed to handle high data
rate transfer when interfacing with HD
Audioor external analog codecs. There
are two on-chip tri-color PWM LEDs and
a PIC controller which is retaskable to
support various communication protocols
over 24 programmable GPIOs.
The device integrates advanced low-
power techniques, such as DC-DC
converters, Power Gating, Power
Retention, Low-Vdd Standby, Dynamic
Voltage Scaling (DVS) and Adaptive
Voltage Scaling (AVS), which employ
voltage control to manage power. In
addition, frequency scaling mechanisms
can also be used to reduce the power
consumption further.
CX20805 comes bundled with advanced
signal processing routines, free of
royalties, for customers interested in
developing their own proprietary
algorithms for different applications. This
package includes CAPE optimized
implementations of filter banks,
Equalizers, Sampling Rate Converter
(SRC), a small footprint Operating
System (etc.).
The Configuration Toolbox allows for fast
configuration of the various signal
processing algorithms and performance
optimization. A complete evaluation kit
with reference board and all the
necessary technical documentation and
software is available. An efficient C
compiler is also available for customers
interested in programming the CAPE
Cores.
Samples are available in a small footprint
9x9, 116-pin Dual Row QFN packaging
along with Evaluation kits.
Applications
Unified Communication Peripherals
Telepresence/Unified Communication
Device
All-in-One Speakers/Docking System
LCD Display/Sound Bar
Home Automation/Intercom
Wi-Fi® Phone/Smart Phone Docking
Systems
Mobile Internet Devices, Portable
Navigation Devices, Portable Media
Players
Multimedia IP phone
Embedded applications
Full-duplex Hands-free Telephony
A/V receivers, DVD
Receivers, Set-top Box
After-market Automotive Amplifiers
and Entertainment systems
Bundled DSP Algorithms
(Royalty Free)
Fast Fourier Transforms (FFT)
Finite Impulse Response (FIR) filters
Infinite Impulse Response (IIR) filters
128 band Analysis and Synthesis
Filterbanks
Dual Knee Dynamic Range
Compression (DRC)
Automatic Gain Control (AGC)
Sampling Rate Converter (SRC &
ASRC)
Equalizer (EQ) with flexible number of
bands
Downmixer (Flexible number of
channels)
Amplifier and Mixer (Side Tone
Generation)
Signal generator
Cyclical Buffering Mechanisms
(1)
Conexant rates its DSPs based on the chips using standard voltage with 10 percent margin. DSP
cores are often rated at the typical conditions with overvoltage and no margin. Under these
conditions, CX20805 could easily exceed 1000 MIPS.
Part Number CX20805
Description
High-Performance Low-
Power Digital Audio Signal Processor
CONEXANT [ CONEXANT SYSTEMS, INC ]
