- 60 -
3. TECHNICAL BRIEF
3.24 DCXO
The transceiver contains a fully integrated 26MHz digitally controlled crystal oscillator (DCXO) with
three outputs for the system clock, one output for the GSM baseband and two additional for other
subsystems (GPS, Bluetooth, etc.). The only external part of the oscillator is the crystal itself. The
overall pulling range of the DCXO consists of eight subranges. The subrange closest to the ‘0ppm’ at
the middle AFC-value is selected during the calibration process in the mobile’s production and is used
for the rest of the lifetime. The frequency tuning is performed along the selected subrange by
programming the frequency control word (XO_TUNE) via the three wire bus (“3Wbus”).
3.25 Front End Module control
Implemented in the Transceiver are two outputs for direct control of front end modules with two logic
input pins to select RX- and TX-mode as well as low- and high band operation.
LGE Internal Use Only
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
To Next Page
Loading...
