Highly Integrated 802.11g/b Transceiver Runs On Ultra-Low Power

A single-chip, direct-conversion, ultra-low-power 802.11g/b RF transceiver from Maxim Integrated Products, the MAX2830, integrates a power amplifier (PA), RX/TX/antenna diversity switches, and crystal oscillator circuitry. As the industry’s first transceiver to integrate RX/TX and antenna diversity switches, the device saves 10 mm² of board space and $0.25 of bill-of-materials (BOM) cost versus competing solutions, according to Maxim.

The low cost and small size of the MAX2830 make it ideal for Wi-Fi, PDA, Voice over Internet Protocol (VoIP), and cellular handset applications. The chip also integrates digitally controlled, crystal oscillator circuitry to implement the reference oscillator function, allowing the use of small, low-cost, low-power crystals. Other devices implement this function with higher-cost, larger, external crystal oscillators that consume more current and increase BOM cost by $0.50, according to the company.

The MAX2830 is designed using Maxim's proprietary high-performance silicon-germanium (SiGe) biCMOS process. The transceiver operates from a 2.7- to 3.6-V supply, and the power amplifier operates from 2.7 to 4.2 V, which allows the MAX2830 to be powered directly from cell-phone batteries. The receiver consumes 62 mA in receive mode, while achieving a noise figure of only 3.3 dB, enabling receive sensitivity of –75 dBm (64QAM OFDM) without an external low-noise amplifier. Additionally, the transmitter and PA deliver linear transmit power of +17 dBm (64QAM OFDM) after the switch. A 20-µA low-power shutdown mode is available to further save power.

The MAX2830 is available in a small, 7- by 7-mm, leadless 48-pin TQFN-EP package. Pricing starts at $5.97 (1000-up, FOB USA). An evaluation kit is available.