Table 6.20.5-3 Power Threshold Reference - Nuvoton ISD94124BYI Technical Reference Manual

Step 5: Set Deviation Threshold with a value right below Deviation values obtained from step
3
Set deviation threshold DEVTHRE (VAD_CTL3[15:0]) lower than deviation power DEV
(VAD_STATUS1[15:0]) read out values.
Short term power threshold STTHREHWM (VAD_CTL1) and deviation threshold DEVTHRE
(VAD_CTL3[15:0]) can be fine-tuned to achieve the sensitivity to desired human speaking volume.
To reduce sensitivity to background noise, these actions are recommended to perform in certain
combinations only: increase speech trigger alone, or increase speech trigger and speech window
together to reduce sensitivity to background noise. Increasing speech window alone will not help
reduce sensitivity to background noise.
The Reference Table of power threshold as Table 6.20.5-3.
Power Threshold
0x7FFF
dB
0 dB
Power Threshold 0x0067
dB 50 dB
Sep 9, 2019
ISD94100 Series Technical Reference Manual
0x2879
10 dB
0x0020
60 dB

Table 6.20.5-3 Power Threshold Reference

Page 884 of 928
0x0CCC 0x040C
20 dB 30 dB
0x000A 0x0003
70 dB 80 dB
0x0147
40 dB
0x0001
90 dB
Rev1.09