User Guide

Nokia Customer Care System Module

Company Confidential RH-30/RH-31

External accessory regulator

An external LDO Regulator exists for accessory power supply purposes. All ACI-accesso-

ries require this power supply. Regulator input is connected to battery voltage VBAT and

output is connected to Vout pin in the system connector. Regulator is controlled via UPP

(On/Off-function).

Accessory regulator signals

Figure 9: External Accessory regulation

External audio

RH-30/RH-31 is designed to support fully differential external audio accessory connec-

tion by using Pop-Port [TM] system connector. Pop-Port [TM] connector has serial data

bus called ACI (Accessory Control Interface) for accessory insertion and removal detec-

tion and identification and authentication. ACI line is also used for accessory control

purposes. See section ACI, Accessory Control Interface. Audio support from Pop-Port [TM]

system connector:

4-wire fully differential stereo audio (used also FM-radio antenna connection)

2-wire differential mic input

External microphone connection

The external microphone input is fully differential and lines are connected to the UEM

microphone input MIC2P/N. The UEM (MICB2) provides bias voltage. Microphone input

lines are ESD protected.

Creating a short circuit between the headset microphone signals generates the hook sig-

nal. When the accessory is not connected, the UEM resistor pulls up the HookInt signal.

When the accessory is inserted and the microphone path is biased the HookInt signal

decreases to 1.8V due to the microphone bias current flowing through the resistor. When

the button is pressed the microphone signals are connected together, and the HookInt

input will get half of micbias dc value 1.1 V. This change in DC level will cause the Hook-

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)

Accessory

Regulator

UPP

Genio(0)

VBAT

Vout

System Connector