AS3435 datasheet(47/102 Pages) AMSCO

47 / 102 page

ams Datasheet, Confidential: 2014-Jun-13 [v1-30]

AS3415/AS3435 – 47

Detaile d Desc rip t ion

Playback Only Mode

The active noise cancelling feature of the AS3415/35 can also

be disabled with the ANC/CSDA pin. The ANC/CSDA pin has to

be pulled high to enable the ANC function during startup (ANC

MODE). If the pin is connected to ground, the chip enters

playback only mode (PBO MODE) in which the ANC function is

disabled. The operating mode of the line input mute switch, as

well as the mixer input, can be defined in register PBO_MODE.

The microphone amplifier shuts down automatically, but it is

possible to control the operational amplifiers in this mode

separately. Typically only the line input amplifiers and the

headphone amplifier are enabled in the playback only mode.

This very special mode allows the user to disable the ANC

function but still use the line input equalizer function of the

chipset. If this function is not desired you just need to pull the

pin high through a 22kΩ resistor.

Figure 60:

Playback Only Mode Timing Diagram

Playback Only Mode Timing Diagram: The diagram shows the necessary voltages and timings for different

operation modes in Playback Only Mode.

AS3435 Scheda tecnica(PDF) 47 Page - ams AG