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 power-
efficient, 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.
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
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Applications
Mobile Internet Device
Multimedia IP phone
Portable Navigation Device
Portable Media Player
Intercom Systems
CONEXANT [ CONEXANT SYSTEMS, INC ]
