Embed Size (px)
Citation preview
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 1
The eGaN® FET Journey Continues
Alex Lidow Efficient Power Conversion Corporation
GaN on Silicon Technology: Devices and Applications
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 2
Agenda
• Hard Switched Circuits – Buck Converter – Envelope Tracking
• Resonant Circuits – Wireless Power Transmission
• What is in the future?
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 3
Key Applications Today • RF DC-DC “Envelope Tracking” – GaN Enabled • Wireless Power Transmission – GaN Enabled • RadHard • LiDAR • RF Transmission • Network and Server Power Supplies • Point of Load Modules • Solar Micro-inverters • Energy Efficient Lighting • Class D Audio
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 4
0.78
0.8
0.82
0.84
0.86
0.88
0.9
0 5 10 15 20 25
Effic
ienc
y
Output Current (Io)
Generations vs Efficiency
0.78
0.8
0.82
0.84
0.86
0.88
0.9
0 5 10 15 20 25
Effic
ienc
y
Output Current (Io)
Generations vs Efficiency
0.78
0.8
0.82
0.84
0.86
0.88
0.9
0 5 10 15 20 25
Effic
ienc
y
Output Current (Io)
Generations vs Efficiency
GaN Gen 2
GaN Gen 3
Reference: D. Reusch, D. Gilham, Y. Su, and F.C. Lee, C, “Gallium Nitride Based 3D Integrated Non-Isolated Point of Load Module,” APEC 2012
High Frequency Buck Converters CPES Gen 2 CPES Gen 1
GaN
Driver
CPES Gen 3
Cin
T
SR GaN Gen 1
Vin=12V Vo=1.2V Fs=1MHz L=150nH
Si
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 5
Switchnode Peak and Ringing
40 V Si MOSFET~ 7.5 ns
40 V eGaN FET~ 1.5 ns
25 V Si MOSFET~ 5.7 ns
3 V/Div5 ns/Div
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 6
Envelope Tracking (ET)
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 7
Peak to Average Power Ratio
Reference: Nujira.com website
Same average
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 8
Output Power (dBm)
Effect of PAPR
Fixed supply
Peak Power Average Power
Output Probability
Average efficiency only 25 %
PAPR = 0dB Peak efficiency
up to 65%
Increasing PAPR
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 9
Output Power (dBm)
Effect of Envelope Tracking
Average efficiency > 50 % (incl. ET)
Average Power
Output Probability
Envelope Tracking
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 10
• ET power supply topologies vary – Open loop boost – full BW required – Closed loop linear-assisted Buck*
Envelope Tracking Supply
Buck ~ 10% Bandwidth ~ 90% Power
Linear AMP ~ 10% Power Highest 90% of Bandwidth
*Reference: V. Yousefzadeh, et al, Efficiency optimization in linear-assisted switching power converters for envelope tracking in RF power amplifiers, ISCAS 2005
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 11
• Modified an EPC9002 development board
15 AOUT / 1 MHz Single φ Buck
45 VIN
22 VOUT
Common
Output Inductor Before After
11
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 12
Efficiency Results
0
2
4
6
8
10
12
14
16
90%
91%
92%
93%
94%
95%
96%
97%
98%
0 50 100 150 200 250 300 350
Powe
r loss
(W)
Effici
ency
(%)
Output Power (W)
4 MHz Efficiency
1 MHz Efficiency
4 MHz Losses
1 MHz Losses
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 13
Wireless Power
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 14
Wireless Power
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 15
Block Diagram of the Wireless System
PSU
Gate Driver
Gate Driver
Feedback and Basic Control
PSU Matching
Impedance Network
+
24VDC
Source Unit
Resonant Source
Device Unit
Capture Device
Load
Un-Regulated DC output
Matching Impedance
Network
WiTricity Coils
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 16
Experimental System Setup eGaN FETs RF connection
Device Board
Source Coil Source Board
Coil Feedback
Device Coil
25m
m
RF connection
50mm
MOSFET RF connection
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 17
Efficiency as Function of Load Power
54
56
58
60
62
64
66
68
70
72
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Efficiency [%]
Output Power [W]
6.639 MHz, 23.6 Ω load
Vin =8V Vout=6.8V
Vin =22V Vout=18.3V
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 18
What’s in the Future?
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 19
47
25
100
250400
1.00
10.00
100.00
1000.00
0 200 400 600 800 1000 1200 1400
Rate
d R D
S(O
N)m
Ω
Rated VDSS(MAX)
2010
2011 2012 2013
2013 2014
Beyond 600 Volts
500 mΩ 5x6mm PQFN
400 mΩ 5x6mm PQFN
250 mΩ 5x6mm PQFN
150 mΩ 8x8mm PQFN
90 mΩ 8x8mm PQFN
LGA Package
19
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 20
Driver On Board
Beyond Discrete Devices
Full-Bridge with Driver and Level Shift
Discrete FET with Driver
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 21
Summary
• GaN transistors enable exciting new applications such as RF Envelope Tracking and Wireless Power Transmission
• GaN transistors have the potential to replace silicon power MOSFETs in power conversion applications with a low-cost and higher efficiency solution
• eGaN FETs are straightforward to use, but you can’t just drop them into a MOSFET socket. Some R&D is needed – start today!
EPC - The Leader in eGaN® FETs | May, 2013 | PCIM 2013 www.epc-co.com 22
The end of the road for silicon…..
is the beginning of
the eGaN FET journey!
