AS3418 datasheet(26/77 Pages) AMSCO

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AS3418

Functional Description

Datasheet

• PUBLIC

DS000507

• v4-00 • 2020-Jan-23

│ 26

off mode or if the headset runs out of battery. Figure 29 shows the basic music playback path of the

AS3418 with a full battery. In this mode the line input signal is feed to the headphone amplifier. The

integrated bypass switches are automatically disabled in this operation mode.

Figure 29:

Bypass Mode Inactive

Figure 30 shows the AS3418 in off mode with an empty battery. This is basically the same use case

as no battery at all. In this mode the internal bypass switch becomes active. The headphone amplifier

is not powered because the headset has run out of battery and the bypass switch becomes active.

Thus the music signal coming from the 3.5mm audio jack is routed through the ANC chip, without any

power source connected to the device, to the speakers. The integrated bypass switch works even

without any battery connected to the device. It helps to reduce BOM costs and PCB area. Furthermore

it facilitates new industrial designs to ANC solutions.

Music Bypass

BPL

BPR

AGND

LINL

LINR

100%

3.5mm audio jack

HPR

HPL

AS3418 Datasheet(PDF) 26 Page - ams AG