BCM4330 Preliminary Data Sheet
WLAN Radio Subsystem
Section 13: WLAN Radio Subsystem
The BCM4330 includes an integrated dual-band WLAN RF transceiver that has been optimized for use in
2.4 GHz and 5 GHz Wireless LAN systems (but not both simultaneously). It has been designed to provide low-
power, low-cost, and robust communications for applications operating in the globally available 2.4 GHz
unlicensed ISM or 5 GHz U-NII bands. The transmit and receive sections include all on-chip filtering, mixing,
and gain control functions.
Up to eight RF control signals are available to drive the external RF switches and support the addition of
optional external power amplifiers and low noise amplifiers for either or both bands. See the reference board
schematics for further details.
Receive Path
The BCM4330 has a wide dynamic range, direct conversion receiver. It employs high order on-chip channel
filtering to ensure reliable operation in the noisy 2.4 GHz ISM band or the entire 5 GHz U-NII band. Control
signals are available that can support the use of optional external low noise amplifiers (LNA), which can
increase the receive sensitivity by several dB.
Transmit Path
Baseband data is modulated and upconverted to the 2.4 GHz ISM or 5-GHz U-NII bands, respectively. Linear on-
chip power amplifiers are included, which are capable of delivering high output powers while meeting
802.11a/b/g/n specifications without the need for external PAs.
These PAs can be powered directly from VBAT, thereby eliminating the need for a separate PALDO. Closed-loop
output power control is completely integrated.
Several spare RF control signals are available to support the addition of optional external power amplifiers for
either or both bands.
Calibration
The BCM4330 features dynamic on-chip calibration, eliminating process variation across components. This
enables the BCM4330 to be used in high-volume applications, because calibration routines are not required
during manufacturing testing. These calibration routines are performed periodically in the course of normal
radio operation. Examples of this automatic calibration are baseband filter calibration for optimum transmit
and receive performance and LOFT calibration for leakage reduction. In addition, I/Q Calibration, R Calibration,
and VCO Calibration are performed on-chip.
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BROADCOM
BCM4330 Preliminary Data Sheet
April 28, 2011 • 4330-DS304-RI
Page 93
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