Troubleshooting Overview - Nokia RH-44 Series Troubleshooting - Bb

CCS Technical Documentation

Troubleshooting Overview

The baseband module of the RH-44 transceiver is a CDMA dual mode engine. The base-
band architecture is based on the NHP-2 phone, but includes some additional features,
such as MIDI and color LCD.
The baseband consists of three ASICs: Universal Energy Management (UEM), Universal
Phone Processor (UPP), and FLASH 64Megabit.
The baseband architecture supports a power-saving function called "sleep mode". This
sleep mode shuts off the VCTCXO, which is used as system clock source for both RF and
baseband. While in sleep mode, the system runs from a 32 kHz crystal and all the RF reg-
ulators (VR1A, VR1B, VR2, ... VR7) are off. The sleep time is determined by network
parameters. Sleep mode is entered when both the MCU and the DSP are in standby mode
and the normal VCTCXO clock is switched off. The phone is awakened by a timer running
from this 32 kHz clock supply. The period of the sleep/wake up cycle (slotted cycle) is
1.28N seconds, where N= 0, 1, 2, depending on the slot cycle index.
RH-44 supports standard Nokia two-wire and three-wire chargers (ACP-x and LCH-9).
However, the three-wire chargers are treated as two-wire chargers. The PWM control
signal for controlling the three-wire charger is ignored. Charging is controlled by UEM
ASIC and EM SW.
BLC-2 Li-ion battery is used as main power source. BLC-2 has nominal capacity of
1000 mAh.
RH-44 supports Tomahawk accessories. The system connector for the RH-44 phones is
the 14-pin Tomahawk connector. The accessories supported include headset (HDB-4),
loopset (LPS-4), basic handsfree car kit (BHF-1), advanced car kit (CARK-142), USB data
cable (DKU-5), and data/flash cable (DKU-5F). The detection is based on the digital ID
read from the accessories.
This service manual also contains a complete troubleshooting guide for GPS circuitry.
Issue 1 04/2003
Nokia Corporation
Troubleshooting — BB
Confidential
RH-44
Page 5