BCM43362KUBGT Datasheet, PDF (19/84 Pages) Cypress Semiconductor – Single-Chip IEEE 802.11™ b/g/n MAC/Baseband/Radio + SDIO

BCM43362 Data Sheet
Frequency References
Section 3: Frequency References
An external crystal is used for generating all radio frequencies and normal operation clocking. As an alternative,
an external frequency reference driven by a temperature-compensated crystal oscillator (TCXO) signal may be
used. No software settings are required to differentiate between the two. In addition, a low-power oscillator
(LPO) is provided for lower power mode timing.
Crystal Interface and Clock Generation
The BCM43362 can use an external crystal to provide a frequency reference. The recommended configuration
for the crystal oscillator, including all external components, is shown in Figure 4. Consult the reference
schematics for the latest configuration.
Figure 4: Recommended Oscillator Configuration
C
12 – 27 pF
OSCIN
C
OSCOUT
R
12 – 27 pF
Note: Resistor value determined by crystal drive
level. See reference schematics for details.
The BCM43362 uses a fractional-N synthesizer to generate the radio frequencies, clocks, and data/packet
timing. This enables it to operate using numerous frequency references. This may either be an external source
such as a TCXO or a crystal interfaced directly to the BCM43362.
The default frequency reference setting is a 26 MHz crystal or TCXO. The signal requirements and
characteristics for the crystal interface are shown in Table 2 on page 20.
Note: Although the fractional-N synthesizer can support many reference frequencies, frequencies
other than the default require support to be added in the driver, plus additional extensive system
testing. Contact Broadcom for further details.
Broadcom_®
February 13, 2015 • 43362-DS106-R
IEEE 802.11 b/g/n MAC/Baseband/Radio + SDIO
Page 18
BROADCOM CONFIDENTIAL