Reduce DC Pwr Consump in CDMA RF Pwr Amps Thru the LMV225 & Eff Switcher (Rev. A)
This application report presents a simple power tracking technique for efficiency enhancement in CDMA RF power amplifiers. This technique involves the use of a linear-in-dB RF power detector and a DC-DC converter switch. This enhancement scheme switches the DC supply voltage, VCC, of an RF power amplifier into two different levels through a DC-DC converter. Texas Instruments RF power detector LMV225 determines the supply voltage of the RF power amplifier. An off-the-shelf CDMA2000 RF power amplifier can be used in this technique to improve the energy efficiency of the mobile phone.