User Guide

PAMS Technical Documentation System Module & UI
NHM-8NX
Issue 1 05/02 ãNokia Corporation Page 5
Transceiver NHM-8NX - Baseband Module BF4A
This section specifies the baseband module for the NHM-8NX transceiver. The transceiver
board is named BF4A, and all board references used refer to the board version BF4A_20.
The baseband module includes the baseband engine chipset, the UI components and the
acoustical parts for the transceiver.
NHM-8NX is a hand-portable dualband EGSM900/GSM1800 phone, with GPRS (Class-4)
for the Basic/Expression segment, having the DCT4 generation baseband (UEM/UPP) and
RF(MJOELNER) circuitry.
The baseband module is developed, as part of the DCT4 common Baseband. It is based
very much upon the NPE-4 and NHM-7 products, main difference being UI and the audio
circuits.
The mechanical construction is based on the NHM-5 phone.
New features in NHM-8NX are MIDI (polyphonic ringing tones) and DC-out (electrical
interface to A-cover).
NHM-8NX supports both three and two wire type DCT3 chargers. Three wire chargers are
treated like two wire ones. There is no separate PWM output for controlling charger but
it is connected to GND inside the bottom connector.
BLC-2 Li-ion battery is used as main power source for NHM-8. BLC-2 has nominal
capacity of 900 mAh.
Hardware characteristics in brief
• Hi-Res (96x65) illuminated B&W display (BW4)
• Active LCD area: width 30,609mm, height 24.10 mm (pixel size
0.304mm*0.356mm, pixel gap 0,015)
• ESD-proof keymat, with 5 individual keys for multiple key pressing
• Support for internal semi-fixed batteries (Janette type)
• No RTC battery
• Plug-in SIM, supporting 1.8 & 3.0V
• Audio amplifier and SALT speaker for MIDI support
• Ringing volume 100dB @ 5cm (MIDI tones through SALT speaker)
• Internal vibra
• Supports voice dial activation via headset button
• DC-out feature for supporting electrical A-covers
• Only 4 (2+2) TBSF LEDs for keyboard & LCD backlight
• 6-layer PWB, only SMD components on one side
• Li-Ion is the only supported battery technology
Note: 5V SIM cards are no longer supported by DCT-4 generation baseband.