User Guide

CCS Technical Documentation Modules
DTX-3
Issue 1 4/03 Nokia Mobile Phones Ltd. Page 5
Functional Description of DTX-3
Circuit Description
The DTX-3 application module connects the TME-3/TME-4 with the fixed telephone net-
work and/or with any unmanned connection, e.g. telemetry, remote control, security sys-
tems, remote data retrieval.
The Data module baseband blocks provide the MCU, DSP, external memory interface and
digital control functions in the UPP ASIC . Power supply circuitry, charging, audio pro-
cessing and RF control hardware are in the UEM ASIC.
The purpose of the RF block is to receive and demodulate the radio frequency signal from
the base station and to transmit a modulated RF signal to the base station.
Product and Module List
Interfaces and Connectors
Telephone interface /PBX Trunk interface:
Telephone interface /PBX Extension interface:
Name of module Type code
Material
code
Notes
Application module DTX-3 0630596
Transceiver TME-3 0600344
Assembly parts A-cover
B-cover
9458825
9458911
Assembly parts must be ordered as separate spare
parts
Transceiver TME-4 0600342
Signals Value
High Impedance Mode 50V
Ringing Voltage 70VAC
Line Impedance 600 Ω
Signals Value
Off-Hook AC impedance 600 Ω
On-Hook AC impedance 150k Ω
On-Hook DC resistance 10M Ω
Loop DC current Min. 15 mA, max. 120mA