Add to Signal Chain Designer

AD8311:  50 dB GSM PA Controller

Product Details

Product Status:Recommended for New Designs

The AD8311 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 −40°C to +85°C.

Its high sensitivity allows control at low signal levels, thus reducing the amount of power that needs to be coupled to the detector. For convenience, the signal is internally ac-coupled. This high-pass coupling, with a corner at approximately 0.016 GHz, determines the lowest operating frequency. Thus, the source can be dc-grounded.

The AD8311 provides a voltage output, VAPC, which has the voltage range and current drive to directly connect to the gain control pin of most handset power amplifiers. VAPC can swing from 300 mV above ground to within 200 mV below the supply voltage. Load currents of up to 6 mA can be supported.

The setpoint control input is applied to pin VSET and has an operating range of 0.25 V to 1.4 V. The associated circuit determines the slope and intercept of the linear-in-dB measurement system; these are nominally 23.6 mV/dB and −59.7 dBm at 0.9 GHz. Further simplifying the application of the AD8311, the input resistance of the setpoint interface is over 35 MΩ, and the bias current is typically 0.26 μA.

The AD8311 is available in a 6-ball wafer-level chip scale package (WLCSP), 1.0 mm × 1.5 mm, and consumes 7.6 mA from a 2.7 V to 5.5 V supply.


  • Single, dual, and triple band mobile handset (GSM, DCS, EDGE)
  • Transmitter power control


  • Complete RF detector/controller function
  • >50 dB range at 0.9 GHz (-48 dBm to +3 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

Functional Block Diagram for AD8311


Title Content Type File Type
AD8311: 50 dB GSM PA Controller Data Sheet (Rev A, 01/2011) (pdf, 728 kB) Data Sheets PDF
AN-1040: RF Power Calibration Improves Performance of Wireless Transmitters  (pdf, 152 kB) Application Notes PDF
Measurement and Control of RF Power
by Eamon Nash, Analog Devices, Inc.
Technical Articles HTML
Detecting Fast RF Bursts using Log Amps  (pdf, 174 kB)
by Yuping Toh, Analog Devices, Inc.
Technical Articles PDF
Make Precise Base-Station Power Measurements  (pdf, 1764 kB)
(Microwaves and RF, November 2002)
Technical Articles PDF
Log Amps and Directional Couplers Enable VSWR Detection  (pdf, 2223 kB)
by Anil Rachakonda and Larry Hawkins, Analog Devices, Inc. (RF Design, 1/1/2007)
Technical Articles PDF
Measuring VSWR and Gain in Wireless Systems  (pdf)
By Eamon Nash, Analog Devices Inc., (Microwave Journal, Nov 2005)
Technical Articles PDF
Measuring the RF Power in CDMA2000 and W-CDMA High Power Amplifiers (HPAs)  (pdf, 609 kB)
By Larry Hawkins, Analog Devices, Inc. (MPD Digest, Nov. 2005)
Technical Articles PDF
Design a Logamp RF Pulse Detector  (pdf, 338 kB)
by Eamon Nash
(Microwaves & RF, January 1, 2000)
Technical Articles PDF
RF Source Booklet  (PDF, 4353 kB)
RF IC Product Overview - Version P (02/2014)
Overview PDF
Industrial Applications Overview HTML
RAQs index Rarely Asked Questions HTML
What is an RF Detector, and how is it used? FAQs/RAQs HTML
Glossary of EE Terms Glossary HTML

Design Tools,Models,Drivers & Software

Title Content Type File Type
ADI’s ADIsimRF design tool provides calculations for the most important parameters within the RF signal chain, including cascaded gain, noise figure, IP3, P1dB, and total power consumption.
ADIsim Design/Simulation Tools HTML
ADIsimPLL™- Version 3.60.10
ADIsimPLL enables the rapid and reliable evaluation of new high performance PLL products from ADI. It is the most comprehensive PLL Synthesizer design and simulation tool available today. Simulations performed include all key non-linear effects that are significant in affecting PLL performance. ADIsimPLL removes at least one iteration from the design process, thereby speeding the design- to-market.
ADIsim Design/Simulation Tools HTML

Evaluation Kits & Symbols & Footprints

Evaluation Boards & KitsView the Evaluation Boards and Kits page for documentation and purchasing

Symbols and Footprints— Analog Devices offers Symbols & Footprints which are compatible with a large set of today’s CAD systems for broader and easier support.

SampleSample & Buy

Price, packaging, availability

AD8311 Model Options
Price Table Help

The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

content here.
content here.

Review this Product