BC41B143A-DS-002PD Datasheet, PDF (54/89 Pages) List of Unclassifed Manufacturers – BlueCore 4-ROM CSP EDR Single Chip Bluetooth v2.0 + EDR System

Device Terminal Descriptions
11.3 Crystal Oscillator (XTAL_IN, XTAL_OUT)
The BlueCore4-ROM CSP RF local oscillator and internal digital clocks are derived from the reference clock at
the BlueCore4-ROM CSP XTAL_IN input. This reference may be either an external clock or from a crystal
connected between XTAL_IN and XTAL_OUT. The external reference clock mode is described in Section 11.2.
11.3.1 XTAL Mode
BlueCore4-ROM CSP contains a crystal driver circuit. This operates with an external crystal and capacitors to
form a Pierce oscillator.
g_m
-
Ctrim
Cint
Ctrim
Ct2
Ct1
Figure 11.5: Crystal Driver Circuit
BC41B143A-ds-002Pd
This material is subject to CSR’s non-disclosure agreement
Production Information
© Cambridge Silicon Radio Limited 2005
Page 54 of 89