Accessories Interface; System Connector; Introduction; Interface - Nokia NKC-1X Series Technical Documentation Manual

CCS Technical Documentation

Accessories Interface

System connector

Introduction

NKC-1X uses accessories via a system connector.

Interface

The interface is supported by fully differential 4-wire (XMICN, XMICP, XEARN and
XEARP) accessories. NKC-1X supports the HDE-2 inbox headset, HDB-5 Boom Headset,
HDC-5 headset, LPS-3 loopset and the PPH-1 car kit.
HEADINT
An accessory is detected by the HeadInt- line, which is connected to the XEARP inside
the system connector. When an accessory is connected, it disconnects XEARP from
HEADINT, and the UEM detects it and generates an interrupt (UEMINT) to the MCU. After
that, the HOOKINT line is used to determine which accessory is connected. This is done
by the voltage divider, which consists of the phone's internal pull-up and accessory-spe-
cific pull-down. The voltage generated by this divider is then read by the ad- converter of
UEM. The HOOKINT- interrupt is generated by the button in the headset or by the acces-
sory external audio input.
Issue 1 02/03
Figure 6: System Connector
MIC
Nokia Corporation
System Module
GND
VIN
PWMO
XMICP
XMICN
HF
HFC
MICN
NKC-1X
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