wm9714l Wolfson Microelectronics plc, wm9714l Datasheet - Page 41

• Manufacturer Part Number: wm9714l
• Description: Ac?97 Audio Codec
• Manufacturer: Wolfson Microelectronics plc

Pre-Production
VOICE DAC
AUXILIARY DAC
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VXDAC is a 16-bit mono DAC intended for playback of Rx voice signals input via the PCM interface.
Performance has been optimised for operating at 8ks/s or 16ks/s. The VXDAC will function at other
sample rates up to 48ks/s, but this is not recommended.
The analogue output of VXDAC is routed directly into the output mixers. The signal gain into each
mixer can be adjusted at the mixer inputs using control register 18h.
When not in use the VXDAC can be powered down using the Powerdown register bit VXDAC
(register 3Ch, bit 12).
Table 19 VXDAC Control
AUXDAC is a simple 12-bit mono DAC. It can be used to generate DC signals (with the numeric input
written into a control register), or AC signals such as telephone-quality ring tones or system beeps
(with the input signal supplied through an AC-Link slot). In AC mode (XSLE = 1), the input data is
binary offset coded; in DC mode (XSLE = 0), there is no offset.
The analogue output of AUXDAC is routed directly into the output mixers. The signal gain into each
mixer can be adjusted at the mixer inputs using control register 12h. In slot mode (XSLE = 1), the
AUXDAC also supports variable sample rates (See “Variable Rate Audio” section).
When not in use the auxiliary DAC can be powered down using the Powerdown register bit AUXDAC
(register 3Ch, bit 11).
3Ch
Powerdown (1)
18h
VXDAC Output
Control
REGISTER
ADDRESS
12
15
14:12
11
10:8
7
6:4
BIT
VXDAC
V2H
V2HVOL
V2S
V2SVOL
V2M
V2MVOL
LABEL
1
1
010
(0dB)
1
010
(0dB)
1
010
(0dB)
DEFAULT
VXDAC Disable Control
1 = Disabled
0 = Enabled
VXDAC to Headphone Mixer Mute
Control
1 = Mute
0 = No mute
VXDAC to Headphone Mixer
Volume Control
000 = +6dB
… (+3dB steps)
111 = -15dB
VXDAC to Speaker Mixer Mute
Control
1 = Mute
0 = No mute
VXDAC to Speaker Mixer Volume
Control
000 = +6dB
… (+3dB steps)
111 = -15dB
VXDAC to Mono Mixer Mute Control
1 = Mute
0 = No mute
VXDAC to Mono Mixer Volume
Control
000 = +6dB
… (+3dB steps)
111 = -15dB
DESCRIPTION
PP, Rev 3.2, October 2008
WM9714L
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