GaN Amplifiers

Gallium Nitride Wide Band-Gap HEMT

Empower RF has broad experience delivering high power GaN amplifiers into mission critical applications and was a very early adopter of GaN on SiC.. Although Empower has many product lines encompassing state-of-the-art Bipolar, MOSFET, LDMOS and GaAs FET devices, GaN has become the marquee technology for TWT replacement and other applications where improvement of SWaP is desired.

Why GaN Transistors?

The key characteristics that makes Gallium Nitride an enabling technology is its significantly higher power density and greater reliability. GaN's increased power density (W/mm) has enabled Empower to reduce power amplifier sizes, minimize cooling and heat-sink demands and package more power per given volume. With the increased efficiencies that GaN provides, Empower RF delivers more reliable, smaller and lighter broadband power amplifiers.

GaN -more specifically GaN on SiC -provides higher output power, longer pulse widths, and larger duty cycles and significantly higher MTTF than GaN on Si, GaAS HEMT, LDMOS, and MOSFET high power transistors.

• Higher Breakdown voltages 60 to 80 VBRDSS (100-150 Volts)
• Higher Power Density
• Superior Thermal Conductivity
• Example: LDMOS - 12W/sq. mm dissipation vs. GaN - 70W/sq. mm dissipation
• Higher Junction Temperatures > 200°C (+225°C to 250°C)
• Higher Saturated Electron Drift Velocity (higher current delivering capability)
• Lower Intrinsic Capacitance which provides higher input/output device impedances allowing broadband matching
• GaN provides High Gain and Efficiencies (Narrow band 50% to 60%)
• Superior Noise & Linear Power Added Efficiency (PAE)

DEVICE TECHNOLOGY	FREQUENCY COVERAGE	PERFORMANCE ADVANTAGES	TRADE-OFFS
GaN (Gallium Nitride HEMT) High Electron Mobility Transistor	20-6000 MHz broadband 8-12 GHz narrowband 12-18 GHz narrowband 18-40 GHz narrowband Up to 100 GHz Future	Broadband Matching Ultra broadband operation Efficiency Linearity Ruggedness High Power Density	Thermal Resistance RӨjc is High Cost Low P1dB compression point Need Negative Bias Voltage Turn On/Off sequence
LDMOS (Lateral Diffused Metal Oxide Semiconductor FET)	20-1000 MHz broadband 1000-3000 MHz narrowband 3400-3800 MHz narrowband	Dynamic Range Efficiency Linearity Gain Simple Device Biasing Cost	Failure to Fast Pulse Fall Times Low input/output impedance Difficult to broadband match Failure to high power peaks Cautious under load VSWR
MOSFET VMOS, DMOS (Metal Oxide Semiconductor FET)	20-100 MHz 100-500 MHz 500-1000 MHz	Dynamic Range Simple Device Biasing Ruggedness Fast Digital waveforms Handles peak power levels	Ultra Broadband Matching Upper Frequency Limit Linearity Efficiency Gain
GaAsFET (Gallium Arsenide MESFET) Metal Semiconductor FET	500-3000 MHz broadband 2000-4000 broadband 2-6 GHz narrowband 6-12 GHz narrowband 12-18 GHz narrowband 18-40 GHz narrowband	Linearity Ruggedness Fast Digital waveforms Handles peak power levels	Efficiency Low Gain Cost Availability Need Negative Bias Voltage Turn On/Off sequence
Bipolar (Silicon)	1-30 MHz 20-100 MHz 100-500 MHz 1200-1400 MHz 2000-3000 MHz narrowband 3000-3500 MHz narrowband	Proven Pulse Capability Highest Power Packaged Device Ruggedness Fast Digital waveforms Handles peak power levels Efficiency Class C Low Frequency operation	Ultra Broadband matching Efficiency Low Gain Linearity Biasing circuit

Denotes best choices in this performance range.

Denotes best choices in this performance range.