Rainbow Electronics AT73C246 - Manual (Page 57)

57
11050A–PMAAC–07-Apr-10
AT73C246
12.4 Audio Controller
The audio controller sequences the power-up and power-down of the audio codec sub-functions
(Mic.amp / ADC / DAC / …). During these transitioning phases, the controller also manages the
gain steps to fade them in and out, thus providing smooth operation.
Depending on the application, two modes are provided:
1. Automatic path control
Dedicated to the major audio path scenarios (those described in Table 13-25 on page 95 ), this
mode enables the whole audio path setup only via "PATHSEL" bits in register AUTOSTART
(0x10).
2. Custom path control
Dedicated to audio path scenarios not described in the previously mentioned table, this mode
brings the flexibility to start manually the audio sub-functions.
The following figure shows the global context of the audio codec control.
Figure 12-3. Audio Codec Typical Control Sequence
Apply Supply
& MCLK
Configure
Analog & Digital
Interfaces
2
Unmute Codec 3
Start Audio
Codec in
Standby
4
Software
Wait
5
Custom path
control
6 Automatic path
control
Shutdown
Audio Codec
8
Unset
DCBLOCK bit 9
Remove MCLK
& supply
10
1
7
Registers to set :
- AUDIO_CONTROL (0x11)
(Set DCBlock bit here)
- MIC_CONTROL (0x12)
- DAI_CONTROL (0x13)
- FRAME_CONTROL (0x14)
Register to set :
- MUTE (0x15)
Register to set :
- AUTOSTART (0x10)
Typically 350ms.
- See VMID section.
Registers to set
- See dedicated sections.
Register to set :
- AUTOSTART (0x10)
Software
Wait
At least 1s.
- See “Power-off Time”
section.
Register to set :
- AUDIO_CONTROL (0x11)
- See “AC/DC coupled load
management” section.