User Guide

CCS Technical Documentation 2 - System Module
RH-26
Issue 1 02/04 ©Nokia Corporation Page 39
The baseband circuitry is located on the other side of the board, which is shielded with a
metallized frame and ground plane of the UI-board.
Maximum height of the RF components on the PWB is 1.8 mm. Heat generated by the
circuitry is carried off via the PWB ground planes and metallic shields.
Main technical specifications
Nominal and maximum ratings
*) Normal cut off battery voltage is 3.04V but minimum battery voltage level for RF is
2.95V.
RF frequency plan
The VCO operates at the channel frequency multiplied by two or four depending on the
frequency band of operation. This means that the baseband modulated signals are
directly converted up to the transmission frequency and the received RF signals directly
down to the baseband frequency. In addition, the circuit implementation of the fre-
quency dividers in an integrated circuit offers a good topology for 90 degrees phase
shifter which is needed in the IQ-modulator and -demodulator.
Parameter Rating
Battery voltage nominal 3.7 V
Battery voltage maximum 4.2 V
Battery voltage minimum 3.1 V *)
Regulated supply voltage 2.78+/-3% V
Voltage reference 1.35+/-1.2% V
Operating temperature range
-10...+55 C
o
-25...+70 C
o
reduced performance,
no damage