WM8350GEB/V Wolfson Microelectronics, WM8350GEB/V Datasheet - Page 67

• Manufacturer Part Number: WM8350GEB/V
• Description: Audio CODECs Audio CODEC plus pwr management
• Manufacturer: Wolfson Microelectronics

Specifications of WM8350GEB/V

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Production Data
w
13.4.5
The WM8350 provides a programmable, low-noise bias voltage for condenser electret microphones
on the MICBIAS pin.
R8 (08h)
Power Mgmt 1
R74 (4Ah)
Mic Bias
Control
Note: MICB_ENA can be accessed through R8 or through R74. Reading from or writing to either
register location has the same effect.
Table 23 Controlling the Microphone Bias Voltage
13.4.6
The WM8350 provides two additional analogue input pins, IN3L and IN3R, for line-level audio or
“beep” signals. Each pin has a simple input buffer whose output signal can be digitised in the audio
ADC and/or mixed into the output signal path. The Right input IN3R may also be connected to the
Output Beep Mixer, for output on OUT2R (see Table 42). The input buffers have a nominal default
gain of -1 (0dB).
Figure 38 Auxiliary Input Buffers
ADDRESS
IN3R
IN3L
MICROPHONE BIASING
AUXILIARY INPUTS (IN3L AND IN3R)
IN3R_SHORT, R73[14]
IN3L_SHORT, R73[6]
BIT
15
14
4
20k
20k
MICB_ENA
MICB_ENA
MICB_SEL
LABEL
Vmid
Vmid
DEFAULT
-
+
-
+
20k
20k
0
0
Microphone bias enable
0 = OFF (high impedance output)
1 = ON
Microphone bias voltage control:
0 = 0.9 * AVDD
1 = 0.75 * AVDD
To:
Right Input Mixer,
Right Output Mixer,
Output Beep Mixer
To:
Left Input Mixer,
Left Output Mixer
DESCRIPTION
PD, March 2010, Rev 4.2
WM8350
67