sta381bws STMicroelectronics, sta381bws Datasheet - Page 113

• 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

STA381BWS
7.5.1
7.5.2
7.5.3
7.5.4
7.5.5
Noise-shaper bandwidth selection
Table 118. Noise-shaper bandwidth selection
AM mode enable
Table 119. AM mode enable
The STA381BWS features an FFX processing mode that minimizes the amount of noise
generated in the frequency range of AM radio. This mode is intended for use when FFX is
operating in a device with an active AM tuner. The SNR of the FFX processing is reduced to
approximately 83 dB in this mode, which is still greater than the SNR of AM radio.
PWM speed mode
Table 120. PWM speed mode
Zero-crossing enable
Table 121. Zero-crossing enable
The ZCE bit enables zero-crossing adjustment. When volume is adjusted on digital zero-
crossing, no clicks are audible.
Soft volume update enable
Table 122. Soft volume update enable
Bit
Bit
Bit
Bit
Bit
2
3
4
6
7
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
RST
RST
RST
RST
RST
0
0
0
0
1
Name
PWMS
NSBW
ZCE
Name
Name
Name
Name
AME
SVE
Doc ID 018937 Rev 2
Register description: Sound Terminal compatibility
‘1’: Volume adjustments only occur at digital zero-crossing
‘0’: Volume adjustments occur immediately
1: Third order NS
0: Fourth order NS
0: Normal FFX operation
1: AM reduction mode FFX operation
0: Normal speed (384 kHz) all channels
1: Odd speed (341.3 kHz) all channels
1: Volume adjustments ramp according to SVR settings
0: Volume adjustments occur immediately
Description
Description
Description
Description
Description
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