Bluetooth Power Amps Integrate Closed Loop Control

The MAX22xx family of 2.4-GHz devices are claimed as the marketÕs first Bluetooth power amplifiers to integrate a closed-loop power control circuit. This circuit allows near constant output power over the full temperature range of -40ûC to +85ûC. Comprised of three devices, the family operates on a supply voltage from 3V to 3.6V and has an input-power range from -4 dBm to +4 dBm. The MAX2244 and MAX2245 deliver an output power up to +22 dBm with 30% power-added efficiency, enabling an output of +20 dBm at the antenna. The MAX2246 provides a +20 dBm output at a 30% reduction in supply current. Features common to all three include an analog power control pin for continuous control of output power from 0 dBm to maximum, a 1 µA shutdown mode, and automatic control of output-power levels during turn on/off. Available in an ultra-chip-scale package (UCSPTM) measuring 1.56 mm x 1.56 mm, prices start at $1.69 each/1,000. An evaluation kit, the MAX2244/ 45EVKIT, is also available. MAXIM INTEGRATED PRODUCTS, Sunnyvale, CA. (800) 998-8800.