User Guide

Reference oscillators

As a reference oscillator for the frequency synthesizers a 38.4MHz VCTCXO (voltage controlled temperature

compensated crystal oscillator) is used.

Regulators

RF is combined with mixed mode ASIC Betty that contains the DA converters for power control and AFC

functions, a slow AD converter for WCDMA power detection and other measurements. It also contains a

regulator for VCTXCO and it’s peripherals.

N7500 contain integrated regulators to supply regulated voltages for their internal circuitry and other RF

parts.

Antenna connections

Device includes two different PIFA type antennas. WCDMA antenna has one feed and one ground contact. GSM

antenna is like normal dual band PIFA antenna (one feed and one ground point) but then there is also extra

ground point, which is connected certain point of the PIFA element. That point has been grounded via PHEMT

switch to certain load so that antenna resonance will spread. This way it is possible to have two different

dual band antennas (900/1800 or 850/1900). All contacts are made with C-clips springs. BT/WLAN antenna

consists of a ceramic resonator.

RM-208

Nokia Customer Care System Module

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