SBAA600 October   2024 TAA5212 , TAC5111 , TAC5112 , TAC5211 , TAC5212

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Voice Activity Detection
    1. 2.1 VAD Configurations
      1. 2.1.1 User, Auto, Intermediate
      2. 2.1.2 VAD With ADC Recording
      3. 2.1.3 VAD Monitoring Channel
      4. 2.1.4 VAD Interrupt Pin
      5. 2.1.5 MICBIAS Enable During PDM Monitoring
      6. 2.1.6 VAD Clock Configurabilty
    2. 2.2 VAD Parameters
      1. 2.2.1 Initial Learning Period
      2. 2.2.2 Hold Over Counter
      3. 2.2.3 Wakeup Wait
      4. 2.2.4 Threshold
  6. 3VAD Performance Results
  7. 4Examples
  8. 5Summary
  9. 6References

1 Introduction

The Voice Activity Detection (VAD) algorithm is a voice-triggered, system wake-up mechanism. The VAD feature enables the device or system (depending on the application) to be in sleep mode: consuming minimal power in the absence of voice activity. The TAx5x1x can generate an interrupt upon the detection of voice activity.Figure 1-1 shows how the VAD responds to voice activity.

VAD ExampleFigure 1-1 VAD Example

The VAD feature is supported on all analog-to-digital converter (ADC) channels of the TAx511x and TAx521x device family, including digital microphone channels, with one channel being monitored at a time. The digital microphone channel is preferred for low-power applications. TI recommends that the audio sampling rate of the device be 8kHz for best performance, however 48kHz is supported if higher fidelity is needed. This application note describes the operation of the VAD, the tunable parameters, and the device configurations required to support VAD.