Perhaps the most inefficient circuit in a cell phone is the RF power amplifier (PA). PAs usually have to operate as class AB devices to provide the linearity necessary for broadband operation, but the resulting efficiency is low.
Agilent's latest PA modules significantly increase efficiency thanks to the company's enhancement-mode pseudomorphic high-electron mobility transistor, or E-pHEMT. The E-pHEMT power modules have the best power-added-efficiency (PAE) spec in the industry, providing up to 30 minutes more life and talk time on a single battery charge.
The ACPM-7813 PA suits dual-mode CDMA/AMPS handsets in the 800-MHz band. The ACPM-7833 PA also fits CDMA/AMPS operation, but in the 1900-MHz PCS band. Both provide a 40% PAE. Power gain is 28.5 dBm with a 3.4-V supply. The ACPM-7891 PA targets tri-band (800, 900, and 1800 or 1900 MHz) GSM handsets. It has a PAE of up to 60% on the low bands and 56% in the higher bands. The gain is 35 dBm on the lower GSM bands and 32.5 dBm on the higher bands, with a 2.2-V supply.
Sample chips are available, with pricing set at $2 in 100,000-unit lots.
Agilent Technologies • www.agilent.com