wm8953 Wolfson Microelectronics plc, wm8953 Datasheet - Page 26

• Manufacturer Part Number: wm8953
• Description: Low Power Stereo Adc With Pll And Tdm Interface Low Power Stereo Adc With Pll And Tdm Interface
• Manufacturer: Wolfson Microelectronics plc

WM8953
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INPUT SIGNAL PATH
The WM8953 has eight highly flexible analogue input channels, configurable in many combinations
of the following:
1. Up to four pseudo-differential or single-ended microphone inputs
2. Up to eight mono line inputs or 4 stereo line inputs
The input paths are mixed together as illustrated in Figure 14.
Figure 14 Control Registers for Input Signal Path
MICROPHONE INPUTS
Up to four microphones can be connected to the WM8953, either in single-ended or pseudo-
differential mode. A low noise microphone bias is fully integrated to reduce the need for external
components.
In single-ended microphone input configuration, the microphone signal is connected to the inverting
input of the PGA (LIN1, LIN3, RIN1 or RIN3). The non-inverting input of the PGAs should be
internally connected to VMID in this configuration. This is enabled via the Input PGA configuration
register settings. In this configuration, LIN2, LIN4, RIN2 or RIN4 may be free to be used as line
inputs.
In pseudo-differential microphone input configuration, the non-inverted microphone signal is
connected to the non-inverting input of the PGA (LIN2, LIN4, RIN2 or RIN4) and the inverted (or
noisy ground) signal is connected to the inverting input (LIN1, LIN3, RIN1 or RIN3).
Any PGA input pin that is used in either microphone configuration should not be enabled as a line
input path at the same time.
PD, January 2009, Rev 4.0
Production Data
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