WM8953ECSSLASHRV datasheet(27/100 Pages) WOLFSON

27 / 100 page

Production Data

WM8953

PD, January 2009, Rev 4.0

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.

Figure 15 Single-Ended Microphone Input

Figure 16 Differential Microphone Input

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 17 LIN1, RIN1, LIN3 or RIN3 as Line Inputs

Figure 18 LIN2 or RIN2 as Line Inputs

Figure 19 Differential Line Inputs

WM8953ECS/RV Datenblatt(PDF) 27 Page - Wolfson Microelectronics plc