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Integrated Power Converters for high Integrated Power Converters for high efficiency RF Systemsefficiency RF Systems

By:Aaron Pereira

Supervisor:Prof. Graham Town & Prof Neil Weste

Department of Electronic Engineering

Macquarie University, NSW, Australia.

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Outline

• Introduction • Background• Solution• Gallium Nitride Material & Devices• PA + High Efficiency Modulator• Triquint 0.25u process & circuits designed• Further Work• Questions

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Introduction

MQ University Department of Electronics:ARC Linkage Grant

•Integrated Power converters for renewable energy systems •100MHz Envelope tracking system using GaN process for base station applications

•Using Triquint existing 0.25u GaN process, to design a high frequency, high efficiency modulator to be integrated into a Power Amplifier (HEPA) module for base stations applications.

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Background

RF Power Efficiency

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Quest for Power, Linearity & Efficiency

VDD

RL

BiasVout

Rs

Vs

Source

InputNetwork

Output Network

RF-in

PowerAmplifier Antenna

RF-out

Q

I

Edge Constellation:3pi/8, rotated 8-PSK

Schematic of PA

Actual Size

Stauth, Sanders, "Power supply rejection for RF amplifiers," (RFIC) Symposium, June 2006 Popovic,Zoya, “High efficiency microwave PA with dynamic power supplies”, ECEN 5014, Spring 2009, University of Colorado, Boulder

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Amplifier Classes- A, AB,B, C, D,E,F Conduction Angle, Efficiency

Niehenke,E, “GaN Power Amplifiers” Niehenke Consulting

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Non Linear PA v Linear PA’sCan’t do amplitude modulation Can- but highly inefficient

Stauth, Sanders, "Power supply rejection for RF amplifiers," (RFIC) Symposium, June 2006

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Average Efficiency

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Solution?Dynamic Power Supplies

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Solution- Research Objective

• HPA +Dynamic power supply MMIC• Use Triquint Semiconductor 0.25u GaN Process

to fabricate a monolithic solution.

MMIC Photo : Courtesy if Stephen Diebold, Karlshue Institute of Technology

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Gallium Nitride – Materials & Devices

RF & Power Electronics

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Properties of GaN

Niehenke,E, “GaN Power Amplifiers” Niehenke Consulting

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Anomalous Behaviour - Traps

Development of virtual gates wrecks havoc in device performance

Ventury, R. “PhD Thesis defence”, UCSB.

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Traps affecting FET performance

Kink effects IDS v VDS

Shift in Threshold VTH

RF Dispersion

ALBAHRANI,S.A , “ CHARACTERIZATION OF TRAPPING IN GALLIUM NITRIDE HEMTS”, PHD THESIS, MACQUARIE UNIVERSITY, AUSTRALIA 2011

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Device Engineering- Field Plates & Passivation

Niehenke,E, “GaN Power Amplifiers” Niehenke Consulting

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MQ- Arbitrary Pulsed Semiconductor Parameter Analyser System (APSPA)

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Pulsed I-V MeasurementsUnderstanding TQTX devices

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Pulsed I-V Measurement (Cont.)

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PA + High Efficiency Modulator

Design Options

TechnologyFCC regulationsCostModulation Schemes

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Power Amplifier Biasing

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Amplifier – Load-linesSwitching PA as Power Converters

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Demonstration of Class E amplifier Electrodeless Fluorescent Lamps

Demonstration of Resonant Inverter Circuit for Electrodeless Fluorescent Lamps Using High Voltage GaN-HEMT Wataru Saito*, Tomokazu Domon**, Ichiro Omura*, Tomohiro Nitta*, Yorito Kakiuchi*, Kunio Tsuda*** and Masakazu Yamaguchi* * Semiconductor Company, Toshiba Corp **Toshiba Business and Life Service ***R&D Center, Toshiba Corp1 Komukai Toshiba-cho, Saiwai-ku, Kawasaki 212-8583, Japan Phone: +81-44-549-2603, FAX: +81-44-549-2883, e-mail: wataru3.saito@toshiba.co.jp

13.56 MHz Class E Amplifier 620V/ 1.4 A GaN HEMT – 90% at 9W Output Power

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DC-DC Converter ArchitectureUsing switching PAs

DC-DC Converter fabricated using FET’s non-optimized for power conversion

Popovic,Zoya, “High efficiency microwave PA with dynamic power supplies”, ECEN 5014, Spring 2009, University of Colorado, Boulder

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PA and Modulator Integration Challenges – Power Supply Rejection Ratio (PSSR)

FCC has strict regulations regarding this.

Selection of filters and switching frequencies critical

Stauth, Sanders, "Power supply rejection for RF amplifiers," (RFIC) Symposium, June 2006

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Triquint 0.25u GaN Process & Circuit Designs

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Circuits Design- Ring Oscillators, inverters, tuned amplifiers

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Circuits Designed-MMIC LayoutRing Oscillators, Inverters, Tuned Amplifiers

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Further Work

• Switching PA’s E/F• Class AB PA (16 Weeks)• Filters for noise rejection (8 Weeks)• Integration (20-24 Weeks)• Thermal Issues (16 Weeks)• Testing (14 Weeks)

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Questions?