Synaptics(R) CX20921 Dual-Mic Far-Field Voice Processor SoC AudioSmart(R) Product Brief Standalone 2-Mic Far-Field Subsystem with Integrated Low-Power Wake-on-Voice (WoV) The voice processing chain also supports multiple modes of processing, which are independently optimized for voice communication and automatic speech recognition. The Synaptics CX20921 is a high-performance, far-field voice input processor System-on-Chip (SoC). The CX20921 is the first product in this category with an integrated voice trigger function that supports a low system power Wake-on-Voice (WoV) function. The device includes two 24-bit microphone Analog-to-Digital Converters (ADCs), a powerful dual core 32bit hardware Digital Signal Processor (DSP), and integrated power management. When ADC and DSP are active in the Wake-on-Voice (WoV) mode, the device consumes less than 70mW, which is well below the 0.5W EC 1275/2008 requirement for standby power. Combined with Synaptics AudioSmart(R) far-field voice input processing software suite, including Smart Source Pickup (SSP) noise suppression and full-duplex stereo Acoustic Echo Cancellation (AEC), the CX20921 is the ideal turnkey solution for adding voice control, voice search, and Voice over Internet Protocol (VoIP)/speakerphone functionalities to SmartTV, SetTop Box (STB), Smart appliances, digital assistants, and automotive hands-free control and communication systems. The CX20921 device supports a microphone array with up to two synchronized ADCs and programmable preamplifiers. Each pre-amplifier is paired with a dedicated bias supply to eliminate crosstalk. The entire input path guarantees 106dB dynamic range, which maximizes speech-to-noise ratio with low boost and prevents microphone saturation. System Block Diagram Key Features * * * * Low-power WoV mode with embedded third-party voice wake-up engine Enables high-performance Automatic Speech Recognition (ASR) and excellent voice clarity with only two mics using Synaptics' AudioSmart voice input processing software, which includes: o SSP noise suppression o Full-duplex stereo AEC Compatible with multiple leading embedded and serverbased speech recognition vendors Dual far-field, 24-bit, 106dB dynamic range ADCs with mic pre-amplifier: o Enables low mic gain for far-field signals without saturation for loud near field signals Applications * * * * * Voice-controlled Smart TV/STB Smart Bluetooth/WiFi speaker Voice interactive smart appliances Internet of Things (IoT) devices Automotive hands-free control/communication Synaptics' proprietary far-field AudioSmart software leverages the built-in hardware to deliver a superior voice interactive experience in the most challenging room environments. Published November 7, 2017. Copyright (c) 2017 Synaptics Incorporated. All rights reserved. PN: 190-000283-01 Rev. A Synaptics(R) CX20921 Dual-Mic Far-Field Voice Processor SoC AudioSmart(R) Product Brief Additional Features * * * * * * * * * * Raw audio sample rates from 8kHz ~ 96kHz 0.125dB analog front-end gain resolution Dedicated microphone bias for low crosstalk Dual serial data interface--I2S/PCM USB full-speed, 2.0 UAC compliant, asynchronous data transfer Asynchronous SRC and sync buffers I2C and UART control interface SPI Flash interface Integrated DC-DC converter for power management 7x7mm 60 QFN package, RoHS compliant Ordering Information Ordering Part Number Part Number Description Package Conditions CX20921-21Z CX20921 Dual Mic Far-Field Voice Processor SoC 60 QFN 7x7mm 0 to 70C CX20921-99Z CX20921 Dual Mic Far-Field Voice Processor SoC (Adds extended temperature range support) 60 QFN 7x7mm -40 to 85C The devices in this publication are lead-free (Pb-Free) and China RoHS compliant. Contact your local Synaptics sales office for advanced software options. Trademarks Synaptics, the Synaptics logo, and AudioSmart, are trademarks or registered trademarks of Synaptics Incorporated or its affiliates in the United States and/or other countries. Notice Use of the materials may require a license of intellectual property from a third party or from Synaptics. This document conveys no express or implied licenses to any intellectual property rights belonging to Synaptics or any other party. Synaptics may, from time to time and at its sole option, update the information contained in this document without notice. INFORMATION CONTAINED IN THIS DOCUMENT IS PROVIDED "AS-IS," WITH NO EXPRESS OR IMPLIED WARRANTIES, INCLUDING ANY IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, AND ANY WARRANTIES OF NON-INFRINGEMENT OF ANY INTELLECTUAL PROPERTY RIGHTS. IN NO EVENT SHALL SYNAPTICS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES ARISING OUT OF OR IN CONNECTION WITH THE USE OF THE INFORMATION CONTAINED IN THIS DOCUMENT, HOWEVER CAUSED AND BASED ON ANY THEORY OF LIABILITY, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, AND EVEN IF SYNAPTICS WAS ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. IF A TRIBUNAL OF COMPETENT JURISDICTION DOES NOT PERMIT THE DISCLAIMER OF DIRECT DAMAGES OR ANY OTHER DAMAGES, SYNAPTICS' TOTAL CUMULATIVE LIABILITY TO ANY PARTY SHALL NOT EXCEED ONE HUNDRED U.S. DOLLARS. Published November 7, 2017. Copyright (c) 2017 Synaptics Incorporated. All rights reserved. PN: 190-000283-01 Rev. A