User Guide

CCS Technical Documentation 2 - System Module
RH-26
Issue 1 02/04 ©Nokia Corporation Page 33
Figure 13: Pop-Port
TM
system connector (charger plug socket & system connector)
ACI
ACI (Accessory Control Interface) is a point-to-point, bi-directional serial bus. ACI has
two main features: 1) The insertion and removal detection of an accessory device 2) act-
ing as a data bus, intended mainly for control purposes. A third function provided by ACI
is to identify and authenticate the specific accessory which is connected to the system
connector interface.
External accessory regulator
An external LDO Regulator is needed for accessory power supply purposes. All ACI-acces-
sories require this power supply. Regulator input is connected to battery voltage VBAT
and output is connected to Vout pin in system connector. Regulator is controlled via UPP
(On/Off-function).
Figure 14: Accessory power supply diagram
Table 23: Accessory regulator signals
External audio
RH-26 is designed to support fully differential external audio accessory connection. A
headset can be directly connected to the system connector. Only mono audio is sup-
ported. With RH-26, two different kinds of headsets can be used: stereo or mono head-
set.
Headset implementation uses separate microphone and earpiece signals. The accessory is
detected by the HeadInt signal when the plug is inserted. Normally when no plug is
present, the internal pull-down on the HF pin pulls down the HeadInt signal. Because of
Signal Min Nom Max Note
Vout 2.70V 2.78 2.86V I
max
= 150mA
GenIO(0) 1.4 1.8 1.88
0.6
High (ON)
Low (OFF)
Accessor
y
Regulator
UPP
Genio(0)
VBAT
Vout
System Connector