wm8953 Wolfson Microelectronics plc, wm8953 Datasheet - Page 27

• 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

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Production Data
Figure 17 LIN1, RIN1, LIN3 or RIN3 as Line Inputs
Figure 19 Differential Line Inputs
The gain of the input PGAs is controlled via register settings. Note that the input impedance of LIN1,
LIN3, RIN1 and RIN3 changes with the input PGA gain setting, as described under “Electrical
Characteristics”. (Note this does not apply to input paths which bypass the input PGA.) The input
impedance of LIN2, LIN4, RIN2 and RIN4 does not change with input PGA gain. The inverting and
non-inverting inputs are therefore not matched and the differential configuration is not fully
differential.
LINE INPUTS
All eight analogue input pins may be configured as line inputs with up to six single-ended inputs
available, and up to four pseudo differential inputs.
LIN1, LIN3, RIN1 and RIN3 can operate as single-ended line inputs to the Input PGAs to provide
high gain if required for small input signals. In this configuration the non-inverting input of the PGAs
should be internally connected to Vmid.
LIN2 and RIN2 can operate as line inputs to the Input PGAs LIN12 and RIN12 or directly to the input
mixers. Direct routing to the mixers minimises power consumption by reducing the number of active
amplifiers in the signal path.
LIN4 and RIN4 should only be used as part of a differential line input with LIN3 and LIN4. Up to four
differential line inputs can be connected to LIN1+LIN2, LIN3+LIN4, RIN1+RIN2 and RIN3+RIN4.
Figure 15 Single-Ended Microphone Input
Figure 18 LIN2 or RIN2 as Line Inputs
Figure 16 Differential Microphone Input
PD, January 2009, Rev 4.0
WM8953
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