CX20745 Low Power I2S Audio CODEC AudioSmart™ Product Brief Capless Headphone/Headset, Class D, Digital Microphone, EQ/DRC, Microphone AGC, Hardware Volume Control The SoC is packaged in an environmentally-friendly, RoHS/green-compliant 48-pin QFN package. Applications • • • • Consumer electronics embedded audio Mobile Internet device Web tablet device Smartbook System Block Diagram SENSE_A MIC BIAS 50mW Capless HP Out 32 7 50mW Capless HP Out 32 7 Bias Generator 2W Class-D 47 Line/Mic In M ADC Conexant Confidential • www.conexant.com • 005PBR00 AGC M 3 + Line/Mic In M ADC 3 M AGC PWM Out Five Band EQ DRC Five Band EQ DRC DAC Fault 2W Class-D 47 DAC 10K Line 5.0V_IN 3.3V LDO 3.3V_FILT 3.3V_IN 1.8 V LDO PCM/I2S 1.8V_FILT PCM/I2S TX_DAT I2C Slave TX_WS/SYNC Clock Circuitry BIT_CLK Master Clock M Digital Mic RX_DAT MIC Clock PWM Out 10K Line M MIC Data SCL The CX20745's power-efficient and flexible class-D amplifier drives up to 2W into four speakers with a 5V supply, or 1W with a 3.3V supply. The SPoC operates at 2.2mA in stand-by mode and 0.5mA in sleep mode, which enhances battery-operated devices through low power consumption and low heat generation. The device supports industrial temperatures of –40~85°C. Jack Sense RX_WS/SYNC The chip features high-performance multi-bit DACs for speaker output, multi-bit high performance ADCs that support mono or array microphones or one stereo line input, capless headphone output, and a range of digital and analog input/output channel selections for flexible routing and mixing. The CX20745 contains a pair of ProCoustic™ headphone drivers that support a fullrange frequency response at 98dB dynamic range and headset jack support, which lowers the BOM cost by eliminating the need for external jack sense, an external amplifier, and DC-blocking capacitors. The CODEC supports four conductor-type OMTP headset jacks with bias sensing for external headset control. All output ports feature Conexant's PopShield DC cancellation to eliminate audio pops and clicks that often occur during power state transitions. BIT_CLK The CX20745 is one of Conexant's embedded audio solutions specifically designed for compact consumer electronics such as mobile Internet devices, Smartbooks, and web tablets. The low-power, energyefficient device features a proprietary in-line configurable DSP, CODEC, stereo filterless class-D amplifier with spread spectrum EMI dispersion technology, capless headphone driver, and I2S interface in a cost-effective single-chip package. The DSP runs a suite of turnkey audio post-processing effects for enhanced sound quality. The DSP runs a suite of 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. The fully configurable hardware equalizer, dynamic range control, and microphone AGC improves performance, maximizes output volume, protects the speakers, and enables far-field audio pick-up by broadening the sound-capture radius for enhanced audio quality. The CX20745 also features hardware digital volume control, which is a feature similar to an infinite volume control knob commonly found in highend audio-visual equipment. SDA Product Overview CX20745 Low Power I2S Audio CODEC | AudioSmart™ Product Brief Key Features • • • • • Class-D amplifier with spread spectrum On-chip DSP Multi-bit DACs/ADCs with fully differential internal signaling PopShield with DC offset cancellation Low power stand-by and sleep CODEC • • Stereo 8-bit/16-bit/24-bit: – DAC supports sample rates capable of 8kHz, 8.018kHz, 11.025kHz, 12kHz, 16kHz, 16.0364kHz, 22.05kHz, 24kHz, 32kHz, 44.1kHz, 48kHz, 88.2kHz, and 96kHz, depending on the master clock ■ 98dB dynamic range ■ –85dB THD – ADC supports sample rates capable of 8kHz, 8.018kHz, 11.025kHz, 12kHz, 16kHz, 16.0364kHz, 22.05kHz, 24kHz, 32kHz, 44.1kHz, 48kHz, 88.2kHz, and 96kHz, depending on the master clock Supports a master clock of 24.576MHz and 22.5792MHz • Data interface: I2S that can be converted to PCM; I2S/ PCM are slave only • • Control Interface: I2C slave only Audio ports: – Stereo analog input port supports up to one single-ended stereo microphone, one differential mono microphone, one single-ended stereo linein, or one differential mono line-in. – Four-conductor OMTP headset set jack compliant with integrated in-line command sensing. Micbias sensing capability for external headset control. Supports sense and switching between the MIC and GND pins. – Stereo class-D amplifier – Stereo capless headphone port – Single-ended analog line output (stereo) – Digital microphone input (stereo) • • • • • • • • • • Class-D amplifier with the following modes of operation: – Up to 2W per channel into 4 with a 5V supply – Up to 1W per channel into 4 with a 3.3V supply – Spread spectrum for EMI protection on the class-D amplifier Line-in loopback mode, where the input signal loops back to the DAC for playback with the EQ PopShield active anti-pop circuit Device can operate in 3.3V only mode Integrated LDO converting 5V to 3.3V, and 3.3V to 1.8V PDM digital MIC interface that supports a clock frequency of 3.072MHz and 1.536MHz Supports industrial temperatures of –40~85°C Jack sense supports up to four jacks CODEC provides independent gain and mute control for both DAC and ADC Four GPIOs—GPIO1 and GPIO2 can be configured for infinity volume control using a rotary encoder DSP • • • Digital parametric equalizer (five bands/channel) Dynamic range control, including a compressor and limiter Microphone AGC Power Management • • Idle mode: 2.2mA with 10ms fast resume Sleep mode: 0.5mA (digital supply only) with 200ms resume www.conexant.com Headquarters: 1901 Main Street, Suite 300 Irvine, CA,92614 General Information: U.S. and Canada: 888-855-4562 | International: 1 + 949-483-3000 © 2014 Conexant Systems, Inc. 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