sta381bws STMicroelectronics, sta381bws Datasheet - Page 94

• Manufacturer Part Number: sta381bws
• Description: Sound Terminal 2.1-channel High-efficiency Digital Audio System Sound Terminal 2.1-channel High-efficiency Digital Audio System
• Manufacturer: STMicroelectronics

Register description: New Map
6.32
94/168
Enhanced zero-detect mute and input level measurement
(address 0x61-0x65)
The STA381BWS implements an RMS-based zero-detect function (on serial input interface
data) able to detect in a very reliable way the presence of an input signal, so that the power
bridge outputs can be automatically connected to ground.
When active, the function will mute the output PWM when the input level become less than
“threshold-hysteresis”. Once muted, the PWM will be unmuted when the input level is
detected greater than “threshold+hysteresis”.
The measured level is then reported (for each input channel) on registers ZCCCFG1 -
ZCCCFG2, ZCCCFG3 - ZCCCFG4 according to the following equation:
Table 89.
reserved
N/A
N/A
N/A
N/A
D7
D7
D7
D7
D7
0
ZMTH[2:0]
000
001
010
011
100
101
110
111
Zero-detect threshold
reserved
N/A
N/A
N/A
N/A
D6
D6
D6
D6
D6
0
Value_in_dB = 20*Log
reserved
N/A
N/A
N/A
N/A
D5
D5
D5
D5
D5
0
Doc ID 018937 Rev 2
N/A
N/A
N/A
N/A
D4
D4
D4
D4
D4
0
RMS_CH0[15:8]
RMS_CH1[15:8]
RMS_CH0[7:0]
RMS_CH1[7:0]
HSEL[1:0]
10
Equivalent input level (dB)
(Reg_value/(2
N/A
N/A
N/A
N/A
D3
D3
D3
D3
D3
0
-102
-108
-114
-114
-78
-84
-90
-96
16
N/A
N/A
N/A
N/A
D2
D2
D2
D2
D2
*0.635))
1
ZMTH[2:0]
N/A
N/A
N/A
N/A
D1
D1
D1
D1
D1
1
STA381BWS
N/A
N/A
N/A
N/A
D0
D0
D0
D0
D0
1