User Guide

ACI interface

The ACI (Accessory Control Interface) is a point-to-point, bi-directional, single line serial bus.

It has two main features: the insertion and removal detection of an accessory device and acting as a data

bus between phone and accessory, intended for control purposes. A third function of ACI is to identify and

authenticate the accessory.

VOUT interface

Accessory power is supplied by VOUT, a linear low drop-out regulator in EM ASIC (N2300) providing 2.5V at

90mA maximum when active (0.5mA in sleep).

ACI data passes to and from EM ASIC (N2300) via the HeadDet line. EM ASIC (N2300) connects HeadDet to MBUS

for RAP to access.

Charger interface

Charging control and charge switch are in TAHVO.

If the temperature rises too high and the thermal protection is activated, TAHVO goes to protection mode.

MicroSD interface

The MicroSD card interface is electrically and functionally compatible with SD card interface.

RM-86

Nokia Customer Care System Module

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