AN2760 Datasheet, PDF (1/14 Pages) STMicroelectronics – Using clock distribution circuits in smart phone system design

AN2760
Application note
Using clock distribution circuits in smart phone system design
Introduction
As smart phones become more and more popular in the market, additional features such as
A-GPS, Bluetooth, WLAN and DVB-H are now included in the cell phone design. In all of
these application modules, there is a common need for a master clock which is typically an
external crystal oscillator. With the master clock the data transmitted or received is
modulated to the proper frequency. In this application note, conventional clock trees which
use discrete crystals for different modules or discrete buffer solutions are compared to the
clock solution using the integrated STCD1020/1030/1040 series circuits from
STMicroelectronics (referenced as STCD10x0 throughout this application note, please refer
to the STCD1020, STCD1030, STCD1040 datasheet). The benefits of using STCD10x0 are
illustrated and technical hints are given to help cell phone system designers use the
STCD10x0 clock distribution solution.
July 2008
Rev 1
1/14
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