The MAX2830 direct conversion, zero-IF, RF transceiver is designed specifically for 2.4 GHz to 2.5 GHz 802.11g/b WLAN applications. The MAX2830 completely integrates all circuitry required to implement the RF transceiver function, providing an RF power amplifier (PA), an Rx/Tx and antenna diversity switch, RF-to-baseband receive path, baseband-to-RF transmit path, voltage-controlled oscillator (VCO), frequency synthesizer, crystal oscillator, and baseband/control interface. The MAX2830 includes a fast-settling sigma-delta RF synthesizer with smaller than 20Hz frequency steps and a digitally tuned crystal oscillator allowing use of a low-cost crystal. No I/Q calibration is required; however, the device also integrates on-chip DC-offset cancellation and I/Q errors and carrier leakage-detection circuits for improved performance. Only an RF bandpass filter (BPF), crystal, a pair of baluns, and a small number of passive components are needed to form a complete 802.11g/b WLAN RF front-end solution.
The MAX2830 completely eliminates the need for an external SAW filter by implementing on-chip monolithic filters for both the receiver and transmitter. The baseband filters are optimized to meet the IEEE 802.11g standard and proprietary turbo modes up to 40MHz channel bandwidth. These devices are suitable for the full range of 802.11g OFDM data rates (6Mbps to 54Mbps) and 802.11b QPSK and CCK data rates (1Mbps to 11Mbps). The ICs are available in a small, 48-pin thin QFN package measuring only 7 mm x 7 mm x 0.8 mm.
