WM8900LGEFK/RV Wolfson Microelectronics, WM8900LGEFK/RV Datasheet - Page 32

• Manufacturer Part Number: WM8900LGEFK/RV
• Description: Audio CODECs Ultra Low Power Hi-Fi CODEC
• Manufacturer: Wolfson Microelectronics

Specifications of WM8900LGEFK/RV

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

WM8900
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Figure 13 Differential Microphone Input Configurations
LINE INPUTS
Two pairs of stereo line inputs are available as analogue inputs. Each of these may be an internal
source (e.g. FM radio IC) or an external signal source. These can be mixed with the microphone
input or can be enabled individually in the ADC input path. The Left (Right) channel boost PGA
must be enabled in this configuration. The gain of the boost PGA can be controlled via register
settings, as described in Table 16.
LINPUT3 (RINPUT3) may also be routed directly to the output mixer, including when the boost
PGA is powered down. If a differential microphone connection is used, then only one of the line
inputs is available. For example, if LINPUT1 and LINPUT2 are used as a differential microphone,
then LINPUT3 can be used as a line input
Note that, in this configuration, the input impedance LINPUT2 (RINPUT2) or LINPUT3 (RINPUT3)
changes with the boost gain setting, as described under “Electrical Characteristics”. The input
impedance can be determined for any gain setting as described above for the Single-Ended
microphone configuration, but based upon the boost gain amplification instead of the microphone
input PGA.
A mono input, AUX, is also provided. This input may be mixed with the Left and Right channel ADC
inputs and may also be routed directly to the output mixers. The gain of this input on the ADC input
path is described in Table 16.
The external connections for this configuration and the required register settings are detailed
below:
•
•
•
LINPUT2 (RINPUT2)
LINPUT3 (RINPUT3)
AUX
PD, August 2008, Rev 4.0
Production Data
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