AudioSmart® CX20924 4-mic Far-Field Voice Input Processor SoC

Four-Microphone Far-Field Input Subsystem with Integrated Low-Power Wake Word

The Synaptics CX20924 is a high-performance, 4-mic far-field voice input processor System-on-Chip (SoC). The CX20924 is the first product in this category with an integrated voice trigger function that supports a low system power Wake-on-Voice (WoV) function and 360-degree Smart Source Locator (SSL) that detects user's location around the device.

The device includes a Pulse Density Modulated (PDM) interface with digital decimation filters that supports up to four high-performance digital microphones, a powerful dual core 32-bit hardware Digital Signal Processor (DSP), and integrated power management.

Combined with Synaptics’ AudioSmart® far-field voice input processing software suite, including four-microphone Smart Source Pickup (SSP) noise suppression and full-duplex Acoustic Echo Cancellation (AEC), the CX20924 is the ideal turnkey solution for adding voice control, 360-degree SSL, voice search, and Voice over Internet Protocol (VoIP)/speakerphone functionalities to SmartTV, Smart Speakers, Set-Top Box (STB), Smart appliances, and many tabletop consumer electronics devices.

The CX20924 device supports four digital microphones using two stereo digital PDM microphone external interfaces. Each Digital Microphone Interface (DMIC) supports sample rates from 8kHz to 96kHz. The CX20924 assists manufacturers and developers to prototype and develop Amazon Alexa™-enabled devices.

Synaptics’ proprietary far-field AudioSmart algorithms leverage the built-in hardware to deliver a superior voice interactive experience in the most challenging room environments. The voice processing chain also supports multiple modes of processing, which are independently optimized for voice communication and automatic speech recognition.

When the PDM microphone and DSP are active in the WoV mode, the device consumes less than 70mW, which is well below the 0.5W EC 1275/2008 requirement for standby power.

System Block Diagram

Applications

• Voice-controlled Smart TV/STB
• Smart Bluetooth/Wi-Fi speaker
• Voice interactive smart appliances
• Internet of Things (IoT) devices

The devices in this publication are lead-free (Pb-Free) and China RoHS compliant.
Contact your  local Synaptics sales office for advanced software options.