
Analog Devices
GENERAL DESCRIPTION
The AD8315 is a complete low cost subsystem for the precise control of RF power amplifiers operating in the frequency range 0.1 GHz to 2.5 GHz and over a typical dynamic range of 50 dB.
It is intended for use in cellular handsets and other battery operated wireless devices. The log amp technique provides a much wider measurement range and better accuracy than controllers using diode detectors. In particular, its temperature stability is excellent over a specified range of −30°C to +85°C.
FEATURES
Complete RF detector/controller function
>50 dB range at 0.9 GHz (−49 dBm to +2 dBm, re 50 Ω)
Accurate scaling from 0.1 GHz to 2.5 GHz
Temperature-stable linear-in-dB response
Log slope of 23 mV/dB, intercept at −60 dBm at 0.9 GHz
True integration function in control loop
Low power: 20 mW at 2.7 V, 38 mW at 5 V
Power-down to 10.8 μW
APPLICATIONS
Single, dual, and triple band mobile handset (GSM, DCS, EDGE)
Transmitter power control