CONEXANT CX20703

Audio
Speakers-on-a-Chip
Speakers-on-a-Chip with On-Chip Voice/Audio DSP,
Integrated I2S/I2C Codec, and PWM Class-D Amplifier
CX20703
Conexant’s portfolio includes a comprehensive suite of semiconductor
solutions for communications and consumer applications.
The CX20703 is one of Conexant’s Speakers-on-a-Chip (SPoC) solutions with
the proprietary on-chip Digital Signal Processor (DSP), Codec, Class-D/PWM
(Pulse-Width Modulator) driver, and I2S and I2C interfaces in a cost-effective
single-chip package. The solution features a suite of turnkey audio and voice
enhancement algorithms designed for applications such as Mobile Internet
Device, Multimedia IP Phone, Portable Navigation Device, Portable Media
Player, and Intercom Systems.
The CX20703 offers multiple digital data and control I/O for flexible peripheral or
MCU/MPU connectivity. The device features one 4-wire and one 5-wire digital
audio interface that can be mixed or multiplexed to support dual bi-directional
I2S, Pulse Code Modulation (PCM), S/PDIF-out with independent sampling rates.
The device can be controlled and configured by both read and write capability
through I2C and Serial Peripheral Interface (SPI).
The device integrates three high-performance 102 dB SNR, 24 bit DACs for
stereo speaker output, capless headphone output, and single-ended/differential
line-output. The analog input paths feature four high-performance 24-bit
ADCs supporting mono or array-microphones, and Auxiliary stereo line-inputs.
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 powerefficient, Class-D PWM output supports an external amplifier to drive large
speakers and offers the option to drive maximum of 2.5 W from the integrated
stereo amplifier.
The CX20703 operates at supply voltages down to 3.3 V for analog and 1.8 V for
the digital core. An advanced power management scheme can be configured to
achieve <5 mW in stand-by mode or <1 mW in deep sleep mode.
The on-chip DSP hardware runs a suite of innovative Conexant proprietary
voice processing algorithms and audio post processing effects that dramatically
improves sound quality and frees-up processing power for other applications
without compromising on cost and future firmware scalability. Conexant’s
acoustic echo cancellation, noise reduction, beam-forming, line echo
cancellation, dynamic range compression, digital equalizer, and 3D effects
deliver a clear, rich and full sound experience to the end user. The embedded
SPoC Configuration Toolbox allows designers to quickly adjust and optimize
audio performance on the target system.
The CX20703 eliminates the need for a mulitiple chip reference design, making
it easy and economical for maufacturers to design products for high quality
audio and voice applications.
Applications
•
•
•
•
•
Mobile Internet Device
Multimedia IP phone
Portable Navigation Device
Portable Media Player
Intercom Systems
Distinguishing Features
• 24-bit DAC/ADC, SNR 102 dB, THD - 92 dB at 48 kHz 3.3 V
• Configurable on-chip proprietary DSP
–Subband acoustic echo suppression and cancellation
–Subband line echo cancellation
–Array mic beam-forming
–Noise reduction
–Dynamic loudness adaptor
–Mic auto gain control
–Digital parametric equalizer (10 bands/
channel)
–Dynamic range compression
–3D Expander (Phantom mode and Immersion mode)
• 4-wire and 5-wire digital audio I/O (I2S/PCM/
SPDIF), supporting full duplex independent sampling rates
• One 3-wire I2C or 4-wire SPI slave interface for external MCU
• 2.5 W x 2 BTL stereo Class-D speaker amplifier, also configurable as a PWM
• Flexible power management
• Audio sample rate: 8, 11.025, 12, 16, 22.05, 24, 32, 44.1, 48, 64, 88.2, 96 kHz
Part Number CX20703
Description
Speakers-on-a-Chip Voice/Audio DSP, Integrated I2S/I2C Codec, and PWM Class-D Amplifier
Audio
Speakers-on-a-Chip
CX20703 Features
CODEC
• 4-wire and 5-wire digital audio I/O (I2S/PCM/SPDIF), supporting full duplex independent sampling rates
• One 3-wire I2C or 4-wire SPI slave interface for external MCU
• Eight GPIO pins
• 2.5 W x 2 BTL stereo Class-D speaker amplifier, also configurable as a PWM
• Output for external feedback-less type Class-D amplifier
• Spread Spectrum for filter-less, low EMI output
• Up to three single-ended line in (convertible to one stereo differential line in and one single-end)
• Two microphones interfaces with on-chip bias supply
• Integrated 50 mW headphone driver with jack sense
• Differential line out
• 24-bit DAC/ADC, SNR 102 dB, THD - 92 dB at 48 kHz 3.3 V
• Audio sample rate: 8, 11.025, 12, 16, 22.05, 24, 32, 44.1, 48, 64, 88.2, 96 kHz
• 90 dB dynamic range with 0.01percent THD+N at 4 Ω load
• 10-bit ADC multiplexed to support analog volume potentiometer and DC level detection
SE or Diff Line In
M
SE or Diff Line In
M
SE Line In
M
SE or Diff Line In
3
Capless HP
Out 32 W
DAC
Capless HP
Out 32 W
Matrix 2
Matrix 1
SE or Diff
10 kW Line
SE or Diff
10 kW Line
MON
ADC
Volume
Voltage
Monitor
EEPROM DATA
UART
EEPROM CLK
SCL
TX_DAT
RX_DAT
WS
MOS/SDA
SPI
I2C Slave
PCM/I2S
TX_DAT
RX_DAT
TX_WS/SDIF
CLK
PCM/I2S
CLK
Jack
Sense
2W Class-D
4 W PWM Out
Controller
DMA
TX
Clock
Circuitry
Matrix 0
Bias
Generator
RX_WS
Sense
DAC
2W Class-D
4 W PWM Out
RX
ADC
XTAL Out
SE or Diff
600 W or 10 kW Line
DSP
GPO 4
MIC In
DMA
GPO 3
ADC
GPO 0
MIC In
XTAL In/
Master In
DAC
DMA
CSN
M
Memory
ADC
GPO 1
SE Line In
3
GPO 2
M
MIC Bus
DSP
ADC
M
SE or Diff Line In
MIC Bus
• Flexible power management
• Variable master clock rates
–7 mW stereo playback (1.8 V supply)
–14 mW record and playback (1.8 V supply)
DSP
• Subband acoustic echo suppression and cancellation
• Subband line echo cancellation
• Array mic beam-forming
• Noise reduction
• Dynamic loudness adaptor
• Mic auto gain control
• Digital parametric equalizer (10 bands/channel)
• Dynamic range compression
• 3D Expander (Phantom mode and Immersion mode)
Configuration Tool
• Fast configuration tool via USB-to-I2C from PC
• Device configuration and DSP parameter adjustment
• Output log for convenient MCU programming
MISO
CX20703 Interface Diagram
The CX20703 is offered in a 76-pin QFN package and is compatible with Conexant’s CX20709 SPoC
Conexant Product Portfolio
Conexant’s comprehensive product portfolio includes solutions for imaging, audio, video, and embedded-modem applications.
© 2009 Conexant Systems, Inc. All Rights Reserved. Conexant and the Conexant
logo are registered trademarks of Conexant Systems, Inc. All other trademarks
are owned by their respective owners. Although Conexant strives for accuracy
in all its publications, this material may contain errors or omissions and is
subject to change without notice.
This material is provided AS IS and without
any express or implied warranties, including merchantability, fitness for a
particular purpose and non-infringement.
Conexant shall not be liable for any
special, indirect, incidental or consequential damages as a result of its use.
09-2884
www.conexant.com
General Information:
U.S. and Canada: (888) 855-4562
International: 1+ (949) 483-3000
Headquarters
4000 MacArthur Blvd.
Newport Beach, CA 92660
Doc# PBR-202404