sta381bws STMicroelectronics, sta381bws Datasheet - Page 68

• 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
6.19.2
68/168
Channel 3 / line output volume (addr 0x1B)
The volume structure of the STA381BWS consists of individual volume registers for each
channel and a master volume register that provides an offset to each channel’s volume
setting. The individual channel volumes are adjustable in 0.5 dB steps from +48 dB to
-80 dB.
As an example, if CH3VOL = 0x00 or +48 dB and MVOL= -12 dB, then the total gain for
channel 3 = +36 dB.
The master mute, when set to 1, mutes all channels at once, whereas the individual channel
mute (CxM) mutes only that channel. Both the master mute and the channel mutes provide
a “soft mute” with the volume ramping down to mute in 4096 samples from the maximum
volume setting at the internal processing rate (approximately 96 kHz).
A “hard (instantaneous) mute” can be obtained by programming a value of 0xFF (255) to
any channel volume register or the master volume register. When volume offsets are
provided via the master volume register, any channel whose total volume is less than -80 dB
is muted.
All changes in volume take place at zero-crossings when ZCE = 1
Configuration register E (addr
possible volume transitions. When ZCE = 0, volume updates occur immediately.
Table 56.
D7
0
11101100 (0xEC)
11101101 (0xED)
11010111 (0xD7)
11011000 (0xD8)
11011001 (0xD9)
11011010 (0xDA)
01011111 (0x5F)
11111111 (0xFF)
00000000 (0x00)
00000001 (0x01)
00000010 (0x02)
01100000 (0x60)
01100001 (0x61)
CH3VOL[7:0]
Channel 3 volume as a function of CH3VOL[7:0]
…
…
…
…
D6
1
D5
1
Doc ID 018937 Rev 2
0x15)) on a per channel basis as this creates the smoothest
D4
0
CH3VOL
D3
0
Hard channel mute
Hard channel mute
+47.5 dB
-59.5 dB
Volume
+0.5 dB
+48 dB
+47 dB
-0.5 dB
-60 dB
-61 dB
-62 dB
-80 dB
0 dB
…
…
…
…
D2
0
D1
0
(Section 6.17:
STA381BWS
D0
0