Audio

Speakers-on-a-Chip

Conexant’s portfolio includes a comprehensive suite of semiconductor

solutions for communications and consumer applications.

The CX20704 is one of Conexant’s Speakers-on-a-Chip (SPoC) embedded

audio solutions for convergence audio entertainment and voice communication

applications. The SPoC features a proprietary on-chip Digital Signal Processor

(DSP), Codec, Mono Class-D Amplifier, I2S and I2C interfaces, high

performance 24-bit DAC’s and ADC’s, a range of digital and analog input/

output channel selections for flexible routing and mixing, and a stereo capless

headphone driver in a cost-effective single-chip package. The solution features

a suite of turnkey audio and voice enhancement algorithms designed for

applications such as Portable Navigation Devices, Portable Media Players,

Multimedia IP phones, and Mobile Internet Devices. This product is part of the

CX2070x SPoC family, which includes CX20702, CX20703, CX20705, CX20706,

CX20707 and CX20709.

The device features multiple high performance 24-bit DACs for stereo speaker

output, multiple 24-bit high performance ADCs supporting mono microphone

and one stereo line input, capless headphone output, support for bi-directional

12S, PCM, S/PDIF-out with independent sampling rates, and a range of digital

and analog 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 power-

efficient mono Class-D amplifier drives a maximum of 2.5 Watt (average) from

the integrated amplifier. The device can be controlled and configured by both

read and write capability through I2C and Serial Peripheral Interface (SPI).

The on-chip Digital Signal Processor (DSP) 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. Key

audio innovations include Subband Acoustic Echo Suppression and Cancellation,

Noise Reduction, Dynamic Loudness Adapter, Mic Auto Gain Control, Digital

Equalizer, Dynamic Range Compression, and 3D effects. The embedded SPoC

Configuration Toolbox allows for fast configuration and performance optimization.

The CX20704 turnkey solution eliminates the need for a multiple-chip reference

design, making it easy and economical for manufacturers to design products

for high quality audio and voice applications. A complete evaluation kit with

reference board and all the necessary technical documents and software is

available.

The SoC is packaged in an environmentally-friendly, RoHS/Green-compliant 76-pin

QFN (Quad Flat No leads) package.

Applications

Portable Navigation Device

•

Portable Media Player

•

Multimedia IP phone

•

Mobile Internet Device

•

Distinguishing Features

• 24-bit DAC/ADC, SNR 102 dB, THD - 92 dB at

48 kHz 3.3 V

• Programmable on-chip proprietary DSP

– Subband acoustic echo suppression and

cancellation

– Noise reduction

– Dynamic loudness adaptor

– Mic auto gain control

– Digital equalizer (10 bands/channel)

– Dynamic range compression

– 3D Expander (Phantom mode and Immersion

mode)

• 5-wire digital audio I/O (I2S/PCM/SPDIF-out),

supporting full duplex independent sampling

rates

• One 2-wire I2C or 4-wire SPI slave interface for

external MCU

• 2.5 W BTL mono Class-D speaker amplifier

• One microphone interface with on-chip bias

supply

• 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 CX20704

Description

Speakers-on-a-Chip with On-chip

Voice/Audio DSP, Integrated I2S/ I2C

Codec, and Mono Class-D Amplifier

Speakers-on-a-Chip with On-chip Voice/Audio DSP, Integrated

I2S/I2C Codec, and Mono Class-D Amplifier

CX20704