WM8959 datasheet(47/155 Pages) WOLFSON

47 / 155 page

Pre-Production

WM8959

PP, May 2008, Rev 3.1

In Differential Mode (AINLMODE=10, AINRMODE=10), no additional volume control is available in

the input signal path, but the Input PGA volume control can be used to adjust the signal level as with

other modes. Both PGAs on the desired channel(s) must be enabled, and the PGA volumes of each

set to the same value for true Differential input characteristics. The PGA Output (LIN12 or RIN12) to

Mixer (INMIXL or INMIXR) path must also be enabled on the desired channel(s) by use of register bit

L12MNB or R12MNB. This configuration is illustrated in Figure 26. The applicable register settings

are shown in Table 11.

CONFIGURATION

1. Select Differential Mode

AINLMODE = 10

2. Enable LIN12 input path

L12MNB = 1

Left Channel Differential

Mode

(DIFFINL to AINLMUX)

3. Set channel volume as required.

Important: The LIN12 and LIN34

volume and mute settings must be

set to the same value. See Table 5

for full definitions of these fields.

LIN12VOL, LIN12MUTE

LIN34VOL, LIN34MUTE

1. Select Differential Mode

AINRMODE = 10

2. Enable RIN12 input path

R12MNB = 1

Right Channel Differential

Mode

(DIFFINR to AINRMUX)

3. Set channel volume as required.

Important: The RIN12 and RIN34

volume and mute settings must be

set to the same value. See Table 5

for full definitions of these fields.

RIN12VOL, RIN12MUTE

RIN34VOL, RIN34MUTE

Table 11 Differential Mode Register Settings

Figure 26 Differential Mode Signal Paths

WM8959 Datasheet(PDF) 47 Page - Wolfson Microelectronics plc