Production Data
WM9715L
AUDIO MIXERS
MIXER OVERVIEW
The WM9715L has three separate low-power audio mixers to cover all audio functions required by
smartphones, PDAs and handheld computers. The diagram below shows the routing of the analogue
audio signals into the mixers. The numbers at the mixer inputs refer to the control register bits that
control the volume and muting for that particular signal.
0Eh [7]
DIFF /
MICL
0/20
dB
0Eh [12:8,4:0]
OUT3VOL
(Reg 16h)
STEREO/
0Eh [14,13]
18h [13]
MICR
MONO
MONOOUT
(PHONE TX)
(Reg 20h)
1Ah [13:11]
10h [13]
PHONE
MIX
10h [12:8,4:0]
LINE_IN
12h [7:4]
0Ah [7:4]
OUT3SRC
(Reg 16h)
PCBEEP
VREF
0Ch [4:0]
M
U
X
OUT3
MONOOUT
PHONE_IN
0Ch [15]
ear
speaker
10h [15]
HEAD
PHONE/
EAR
SPEAKER
MIX
14h [11:7]
18h [15]
18h [12:8,4:0]
1Ch / ALC
STEREO
DAC
HPOUTL
HPOUTR
14h [15:12]
0Ah [15:12]
12h [15:12]
HPVOL
(Reg 04h)
Stereo
headphone /
headset
M
U
X
RECORD
SELECT
INV
(Reg 02h)
PHONE MIX
HEADPHONE MIX
BACK SPKR MIX
10h [14]
-1
LOUT2
ROUT2
18h [14]
BACK
SPEAKER
MIX
M
U
X
AUX
DAC
(12-BIT)
loud
speaker
12h [11:8]
0Ah [11:8]
0Ch [14]
0/20
dB
OUT2VOL
(Reg 02h)
SRC
1Ah [14]
STEREO
(Reg 16h)
ADC
Figure 4 Audio Mixer Overview
HEADPHONE MIXER
The headphone mixer drives the HPOUTL and HPOUTR outputs. It also drives OUT3, if this pin is
connected to an ear speaker (phone receiver). The following signals can be mixed into the
headphone path:
•
•
•
•
•
•
•
PHONE (controlled by register 0Ch, see “Audio Inputs”)
LINE_IN (controlled by register 10h, see “Audio Inputs”)
the output of the Record PGA (see “Audio ADC”, “Record Gain”)
the stereo DAC signal (controlled by register 18h, see “Audio DACs”)
the MIC signal (controlled by register 0Eh, see “Audio Inputs”)
PC_BEEP (controlled by register 0Ah, see “Audio Inputs”)
the AUXDAC signal (controlled by register 12h, see “Auxiliary DAC”)
In a typical smartphone application, the headphone signal is a mix of PHONE and sidetone (for
phone calls) and the stereo DAC signal (for music playback).
PD Rev 4.0 December 2007
35
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
