GaN Power ICs at 1 MHz+:Topologies, Technologies and Performance

PSMA Industry Session, Semiconductors

Dan Kinzer, CTO/COOdan.kinzer@navitassemi.com

March 2017

Power Electronics: Speed & Efficiency are Key

• Speed enables small size, low-cost and faster charging

• Efficiency enables energy savings

• With Silicon or Discrete GaN power devices, you can get one or the other

• With GaN power ICs, you get both at the same time with unequaled Speed & Efficiency

2

Up to

5xEnergy Savings

100x fasterShrink size, weight & cost

Fastest, most efficientGaN Power FETs

>20x faster than silicon>5x faster than cascoded GaNProprietary design15+ pending or issued patents

World’s First AllGaN™ Power ICs

3

First & FastestIntegrated GaN Gate Drivers

>3x faster than any other gate driverProprietary design8+ pending patents

World’s FirstAllGaN™ Power IC

Up to 40MHz switching, 5x higher density & 20% lower system cost

Fastest, most efficientGaN Power FETs

>20x faster than silicon>5x faster than cascoded GaNProprietary design15+ pending or issued patents

First & FastestIntegrated GaN Gate Drivers

>3x faster than any other gate driverProprietary design8+ pending patents

DriverCircuits

Power Devices

The Power of GaN Power ICs... Unequaled Speed & Efficiency

Silicon

DiscreteGaN

GaN Power ICs

PassiveComponents

500kHz

1-10MHz

100kHz85-90%

SwitchingFrequency

Energy Efficiency

88-92%

90-95%

4

GaN Power IC – Fast & Efficient

5

• No overshoots, No spikes, No oscillations , S-curve’ transitions,

• Zero Loss Turn-on (Soft switching) Zero Loss Turn-off (Integrated Gate Drive)

200ns/div

High Side Sync Rect

ZVS soft switching

Zero Loss Turn-off

Low Side Sync Rect

Vgs of Low Side FET

1MHz ZVS

Vds of Low Side FET

200 ns/div

Speed & Integration Eliminate Turn-off Losses

6

Load Current (A)

External drivers• Just 1-2 nH of gate loop

inductance can cause unintended turn-on

• Gate resistors reduce spikes but create additional losses

Integrated GaN drivers (iDrive™)• Eliminate the problem

• Negligible turn-off losses

Turn

-off

Lo

ss (

μJ)

GaN Power IC: Hi-Speed FET, Drivers & More

• Proprietary AllGaN™ technology

• Monolithic integration of GaN FET, GaN Driver, GaN Logic

• 650 V eMode

• 20x lower drive loss than silicon (<35 mW at 1 MHz)

• Driver impedance matched to power device

• Very fast (prop delay and turn-on/off of 10-20 ns)

• Zero inductance turn-off loop

• High dV/dt immunity (200 V/ns) with control

• Digital input

• Complete layout flexibility

7

QFN 5x6mm

10-30V

D. Kinzer, S. Oliver “Monolithic HV GaN Power ICs” in IEEE PELS Power Electronics Magazine, vol. 3, no. 3, pp. 14-21, September 2016

Fast Chargers ... going “GaN Fast”3x Fast Charging with 50% Energy Savings

8

Existing Si-based 15W

100 kHzUp to 6.5 W/in3

88%

Smartphones & Tablets

Fast-charging Drones

AR / VR & Wearables

AllGaN™ 201625W

300-500 kHz11 W/in3

>92%

2x Faster Charging

>1 MHz17.5 W/in3

>95%

AllGaN™ 201725W

3x Faster Charging

2016: Navitas; 2017: Xiucheng Huang, "High Frequency GaN Characterization and Design Considerations," Ph.D Dissertation, Dept. Electr. Eng., Virginia Tech., Blacksburg, VA, USA, 2016.

25W 5W

45W Active Clamp Flyback & AllGaN Power ICs

9

• 94.5% efficient at 220 V (94.2% at 120 VAC, 93.1% at 90 VAC)

• 23.7 W/in3 density (uncased)

• 15.7 mm profile

15.7mm

For further details of ACF, please see APEC 2017 technical paper “Active Clamp Flyback Using GaN Power IC for Power Adapter Applications”, Xue, Zhang

45W CrCM ACF Operation

• Switch-node voltage (VSW), SR FET voltage (VSR), leakage current (iLK) and magnetizing current (ILm)

• 120VAC, 0.2A load, FSW = 210kHz, Circulating Current minimized using Secondary Resonance

10For further details of ACF, please see APEC 2017 technical paper “Active Clamp Flyback Using GaN Power IC for Power Adapter Applications”, Xue, Zhang

45 W ACF: High Efficiency, Cool Temperatures

11

90.0%

90.5%

91.0%

91.5%

92.0%

92.5%

93.0%

93.5%

94.0%

94.5%

95.0%

80 100 120 140 160 180 200 220 240

Effi

cien

cy (

%)

Input Voltage (VAC)

For further details of ACF, please see APEC 2017 technical paper “Active Clamp Flyback Using GaN Power IC for Power Adapter Applications”, Xue, Zhang

AllGaN 2017: 1 MHz, 25 W ACF in 5W Size

• Single-stage EMI

• Navitas GaN Power ICs

• Planar transformer

• DSP (for prototype)

12Xiucheng Huang, "High Frequency GaN Characterization and Design Considerations," Ph.D Dissertation, Dept. Electr. Eng., Virginia Tech., Blacksburg, VA, USA, 2016.

MHz+ 25 W ACF Prototype Performance

13

VGS

(3 V/div)

VDS

(50 V/div)

100 ns/div

FSW=1.5MHz

0.876

0.921

0.933 0.931

0.87

0.88

0.89

0.9

0.91

0.92

0.93

0.94

0 0.25 0.5 0.75 1

Effi

cien

cy

Load Current (A)

2.6MHz

1.5MHz

* Exclude bridge and EMI filter loss

Efficiency vs. Load

Xiucheng Huang, "High Frequency GaN Characterization and Design Considerations," Ph.D Dissertation, Dept. Electr. Eng., Virginia Tech., Blacksburg, VA, USA, 2016.

AllGaN™ 2016150W

300-500 kHz17 W/in3

>93%

2x Higher Density

14

GaN Power ICs enable Hi-Density Adapters3x Higher Density with 50% Energy Savings

Ultra-thin LED TV

All-in-One PCs

Next-Gen Gaming Consoles

Existing Si-based 150W

100 kHz5-10 W/in3

88%

AllGaN™ 2017150W

>1 MHz26.5 W/in3

>95%

3x Higher Density

2016: Navitas + On Semiconductor; 2017: Xiucheng Huang, "High Frequency GaN Characterization and Design Considerations," Ph.D Dissertation, Dept. Electr. Eng., Virginia Tech., Blacksburg, VA, USA, 2016.

150 W, 19 V: GaN Power IC vs. Si

Part# Technology V Pack RDS(ON)(typ. mΩ)

QG(typ. nC)

COSS(er)(typ. pF)

R x QG(mΩ.nC)

R x COSS(er)(mΩ.pF)

STL34N65M5 Si FET 650 8x8 99 62.5 63 6,187 6,237

IPL60R199CP Si FET 600 8x8 180 32 69 5,760 12,420

IPL60R299CP Si FET 600 8x8 270 22 46 5,940 12,420

NV6115 GaN Power IC 650 5x6 160 2.5 30 400 4,800

NV6117 GaN Power IC 650 5x6 110 4 45 440 4,950

GaN Benefit 14x 1.5-2.5x

15

Navitas GaN Power ICs (5x6mm QFN)PFC = 1x NV6117, LLC = 2x NV6115

Si FETs (8x8mm QFN)a) PFC = 1x IPL60R299CP, LLC = 2x IPL60R299CPb) PFC = 1x IPL60R199CP, LLC = 2x IPL60R299CP

For further details of the 150 W, 21 W/in3 board, please see APEC 2017 Industry Session “State-of-the-Art Mobile Charging: Topologies, Technologies and Performance” (Mobile Applications)

Frequency-related Loss Kills Si

16

80

82

84

86

88

90

92

94

96

10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

Effi

cien

cy [

%]

Output Power [W]

+4%

GaNPFC = 110mΩLLC = 160mΩ

220V

120V

90V

Si #1PFC = 270mΩLLC = 270mΩ

220V

88%

89%

90%

91%

92%

93%

94%

95%

Effi

cien

cy (

%)

220V

120V

90V

Powertrain GaN Si #1 Si #2 Si #3

PFC (mΩ) 110 270 180 99

LLC (mΩ) 160 270 270 270

120V

90V

Efficiency vs. Output Power, AC Line Voltage Efficiency vs. AC Line Voltage (150W Full Load)

+5%

PFC = free-running 63-200 kHz, LLC = 300 kHz

AllGaN 2017: MHz 150W Totem-pole + LLC

17

PFC

LLC

IIN_AC

VSW

VGS

200 ns/divILr

VSW

VGS

LLC

0.91

0.92

0.93

0.94

0.95

0.96

80 100 120 140 160 180 200 220 240 260

Input Voltage (Vrms)Ef

fici

en

cy

State-of-the-art (Si)

GaN-based Power Density= 35 W/in3

(Best commercial benchmark= 12W/in3)

GaN based

1 MHz, 3.2 kW Server Supply – 70 W/in3

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• Multi-phase Totem-Pole CrCM + 2-phase Full-Bridge LLC• Input : 220 VAC (47-63 Hz)• Output : 48 V, 3.2 kW• Target Size : 200 x 80 x 41.5 mm (uncased)

• Target Frequency:• PFC = Variable frequency interleaving (500 kHz – 1.5 MHz)• LLC = Fixed-frequency interleaved 1 MHz

• Target Efficiency:• PFC : >99% peak (1)

• LLC : >98% peak (2)

(1) Achieved on Alpha prototype (2) EstimatedPFC Beta version

LLC converter

650V GaN Power ICs

650V GaN Power ICs80V GaN FETs

Quasi-Square Wave PFC Full-range ZVS Operation

• Totem Pole Configuration• Current Mode Control• Constant ZVS current point• Simple rule: only change the

current reference waveforms

0.5

1.0

1.5

2.0fsw(MHz)

00.5TL0

t

100% Load50% Load20% Load

0 2.1 103

4.2 103

6.3 103

8.4 103

0

5 105

1 106

1.5 106

2 106

2 106

0

f.1 t 1( )

f.1 t 0.5( )

f.1 t 0.2( )

f.1 t 0.05( )

0.00840 t

0 2.1 103

4.2 103

6.3 103

8.4 103

0

5 105

1 106

1.5 106

2 106

2 106

0

f.1 t 1( )

f.1 t 0.5( )

f.1 t 0.2( )

f.1 t 0.05( )

0.00840 t

0 2.1 103

4.2 103

6.3 103

8.4 103

0

5 105

1 106

1.5 106

2 106

2 106

0

f.1 t 1( )

f.1 t 0.5( )

f.1 t 0.2( )

f.1 t 0.05( )

0.00840 t

0 2.1 103

4.2 103

6.3 103

8.4 103

0

5 105

1 106

1.5 106

2 106

2 106

0

f.1 t 1( )

f.1 t 0.5( )

f.1 t 0.2( )

0.00840 t

VDC=385V

VAC=240V/RMS

Rload=102ohm

Pload=1450W

Zero Load Soft Start Full Load 1.45kW

19

98.2

98.4

98.6

98.8

99

99.2

99.4

99.6

99.8

100

0 200 400 600 800 1000 1200 1400 1600

Efficiency at 385V/DC, 240V/AC

AllGaN Achieves Over 99% PFC Efficiency

Power(W)

3 GaN in Parallel, Vdd=6V

9.5uH, 7 Turns, Litz 46/660 fmax=1.6MHz

fmax=1.2MHzfmax=0.85MHz

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Wireless Power ... Accelerated

21

AC-DC Adapter88% Efficiency

DC-DC94% Efficiency

Power Amplifier93% Efficiency

Wireless Transfer90% Efficiency

Single-Stage Amplifier90% Efficiency

• 650V GaN Power ICs• 3-stages integrated in 1-stage• 6.78MHz Operation• High-Efficiency

• Multi-stage Efficiency: 77%

• GaN-enabled single stage: 90%

• 20% lower system cost

• 3x faster charging

Existing Silicon-based multi-stage wireless power

22

AC

6.78 MHz Output Direct to Transmitter Antenna

EMI

47-63 HzAC Input

400V Phase-shifted Full Bridge with ZVS Coupled Inductors

GaN Phase-Shift vs. Load

Meets Key System Requirements:

Constant output currentvs. load reactance

AC-RF Single Stage, Efficient & Cost-effective

For further details, please see APEC 2017 technical paper “Single-Stage 6.78 MHz Power-Amplifier Design Using High-Voltage GaN Power ICs for Wireless Charging Application”, Xue, Zhang

Cool AllGaN, No Chance for Silicon

23

ZVS Current-Induced LossDevice Speed

50W Prototype Board:a) Significant potential for further

integration (control & GaN Power IC)b) Thermal performance (50W):

Max GaN Power IC TCASE = 53°C

70%

75%

80%

85%

90%

95%

10 20 30 40 50 60

EFFI

CIE

NC

Y (%

, 11

0V

AC)

OUTPUT POWER [W]

Efficiency from AC line to Transmitter Coil

27 MHz, 40 MHz…

24

Technology VPack(mm)

FSW

(MHz)

Eff.(%)

Power(W)

RF Si (ARF521)500

M17422x22

27.12 91% 150

650QFN5x6

27.12 96% 150

40.00 93% 115

• 50% less loss than RF Si• 16x smaller package• Air-core inductors• Minimal FET loss• Negligible gate drive loss

20ns/div, 150V/div

27.12MHz, φ2 Inverter, VDS of GaN

Class Phi-2 DC/AC converter

GaN Power ICs at 1 MHz+:Topologies, Technologies and Performance

PSMA Industry Session, Semiconductors

Dan Kinzer, CTO/COOdan.kinzer@navitassemi.com

March 2017