CONEXANT CX20671 CX20671-21Z Low-Power Codec SoC With Integrated Class-D Stereo Amplifier for High Definition Audio

 

Conexant's CX20671 HD Audio codec SoC is a low-power,102 dB SNR, high-performance audio codec with integrated 2-WRMS (per channel) stereo speaker amplifier with Spread Spectrum EMI dispersion technology. Two independent pairs of DACs and three independent pairs of ADCs support Multi-Streaming and Real Time Communications applications. The audio fidelity of the device exceeds Microsoft WLP 4.0 Desktop and Notebook Premium Logo requirements. Additionally, the device achieves a high level of integration by featuring an integrated 5 V to 3.3 V Low-dropout (LDO) voltage regulator that guarantees high performance analog audio performance without incurring external BOM, and an integrated 3.3 V to 1.8 V low-dropout voltage regulator used to power internal digital blocks. The device features a ProCoustic capless headphone driver. This high-output power headphone driver delivers 50 mW per channel into a 32 Ω load, eliminating the need for an external headphone amplifier and DC-blocking capacitors, and produces a full range frequency response without sacrificing the output level. The ProCoustic headphone driver provides a true high-definition listening experience from the PC for the audio aficionado. All output ports feature PopShield circuitry that eliminates pops or clicks. The CX20671 also features Conexant's D-Flex power management scheme, which allows the system to exceed the power savings specified in the Intel ECR 15B requirement. The entire audio SOC consumes 16.79 mW during S0-idle. The internal Wake-on-PC-Beep logic resumes the analog paths for the external PC-Beep to propagate through to the output ports. The CX20671 features one single-bit stream digital microphone interface, which allows interfacing to two digital microphones for dual microphone array implementations. The Digital Microphone Interface (DMI) is optimized with a hardware DC-level filter, which compensates for digital microphones with DC offset limitations. Conexant has qualified many digital microphones and listed them on the Approved Vendor List (AVL), providing the OEM and the ODM with more selections and flexibility. The audio codec features an independent SPDIF out supporting sample rates up to 96 kHz, 16-24-bit resolution. The device is compliant with Intel's High Definition Audio Specification (Revision 1.0), as well as the ECR 15B power management scheme.