Post on 29-Jan-2021
www.epc-co.com 1 EPC - The Leader in GaN Technology | September , 2014 |
GaN Transistors for Efficient Power Conversion
Alex Lidow
and David Reusch
Efficient Power Conversion
www.epc-co.com 2 EPC - The Leader in GaN Technology | September , 2014 |
Agenda
• How GaN works and the state-of-the-art
• Design Basics
• Design Examples
• What is in the future?
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How GaN Works and the
State-of-the-Art
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Power Switch Wish List
• Lower On-Resistance
• Faster
• Less Capacitance
• Smaller
• Lower Cost
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Material Comparison
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State of the Art
Theoretical on-resistance vs. blocking voltage capability for silicon, silicon carbide, and gallium nitride.
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GaN Switch
AlGaN
GaN
V
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GaN Switch
AlGaN
GaN
V
Now we have a switch That has high voltage blocking
capability, low on resistance, and is
very, very fast.
Depletion Mode = Normally On
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Device Construction Concept
GaN
Silicon
Protection Dielectric
Drain Source
Gate AlGaN
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What about “Normally Off” devices?
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Cascode GaN Device
Reference: “The Status of GaN Power Device Development at International Rectifier,” PCIM 2012
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Cascode Penalty
Gate
Source
Drain
Cascode devices combine a depletion mode GaN transistor with a low voltage enhancement mode MOSFET
GaN Improves
Si Improves
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Enhancement Mode
A positive voltage from Gate-To-Source establishes an electron gas under the gate
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A positive voltage from Gate-To-Drain also establishes an electron gas under the gate
Body Diode?
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Cross Section of an eGaN® FET
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Electrical Characteristics
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MOSFET
+ QRR
eGaN FET
+ Zero QRR
eGaN FET Reverse Conduction
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On Resistance vs. Temperature
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
2.1
2.2
-50 -25 0 25 50 75 100 125 150
Nor
mal
ized
On
Res
ista
nce
Junction Temperature (°C)
GaN
MOSFET B
About 20%
Difference At 125 °C
eGaN FET
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Threshold vs. Temperature
0.6
0.7
0.8
0.9
1
1.1
1.2
-50 -25 0 25 50 75 100 125 150
Nor
mal
ized
The
rsho
ld V
olta
ge
Junction Temperature (°C)
GaN
MOSFET A
eGaN FET
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eGaN FET Transfer Characteristics
EPC2001
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MOSFET Transfer Characteristics
Source: www.infineon.com
Negative temperature coefficient region of silicon MOSFET
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eGaN FET Safe Operating Area
22
1 ms
10 ms
100 ms
DC
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eGaN FET Safe Operating Area
23
1 ms
10 ms
100 ms
DC
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eGaN FET Capacitances
GaN
Silicon
CGD
CDS
CGS
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Total Gate Charge
EPC2001 = 100 V, 5.6 mΩ typ.
BSC057N08 = 80 V, 4.7 mΩ typ.
BSC057N08NS
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VIN=48 V VOUT=1 V IOUT=10 A fsw=300 kHz L=10 µH eGaN FET T/SR: 100 V EPC2001
MOSFET T/SR: 80 V BSZ123N08NS3G
10 V/ div 20 ns/ div
80 V
Si MOSFET
10.3 mΩ 100 V
eGaN FET
5.6 mΩ
Switching Comparison
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0
1
2
3
4
5
6
0 20 40 60 80 100 120
RD
S(o
n) (m
Ω)
Drain-to-Source Voltage (V)
GaN Improvements
VGS=5 V
Generation 2
2011
Generation 4
2014
2.3x
2.6x
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0
10
20
30
40
50
60
70
80
90
100
0 50 100 150 200 250
FO
M=
QG·R
DS
(on
) (p
C·Ω
)
Drain-to-Source Voltage (V)
Gate Charge FOM
1.4x
1.4x
1.4x
Generation 2
2011
Generation 4
2014
28
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Gate Charge Figure of Merit
0
100
200
300
400
500
600
0 50 100 150 200 250
FO
M=
QG·R
DS
(on
) (p
C·Ω
)
Drain-to-Source Voltage (V)
EPC Gen 4
EPC Gen 2
Vendor A
Vendor B
Vendor C
Vendor D
Vendor E
9.9x
1.3x
4.2x
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0
5
10
15
20
25
30
35
40
45
50
0 50 100 150 200 250
FO
MH
S=
(QG
D+
QG
S2)·
RD
S(o
n) (p
C·Ω
)
Drain-to-Source Voltage (V)
VDS=0.5·VDSS, IDS=20 A
Hard Switching FOM
1.4x
2.4x
2.4x
Generation 2
2011
Generation 4
2014
30
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1
10
100
0 50 100 150 200 250
FO
MH
S=
(QG
D+
QG
S2)·
RD
S(o
n) (p
C·Ω
)
Drain-to-Source Voltage (V)
EPC Gen 4
EPC Gen 2
Vendor A
Vendor B
Vendor C
Vendor D
Vendor E
GaN Transistors
2014
GaN Transistors
2011
Si MOSFETs
2014
VDS=0.5·VDSS, IDS=20 A
Hard Switching FOM
5x
4.8x
8x
31
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Miller Ratio
VDS=0.5·VDSS, IDS=20 A
0
0.5
1
1.5
2
2.5
0 50 100 150 200 250
Mil
ler
Rati
o=
QG
D/Q
GS
1
Drain-to-Source Voltage (V)
EPC Gen 4
EPC Gen 2
Vendor A
Vendor B
Vendor C
Vendor D
Vendor E
2.5x
2.5x
2x
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Soft-Switching Figure of Merit
VDS=0.5·VDSS
0
500
1000
1500
2000
2500
0 50 100 150 200 250
FO
MS
S=
(QG+
QO
SS)·
RD
S(o
n) (p
C·Ω
)
Drain-to-Source Voltage (V)
EPC Gen 4
EPC Gen 2
Vendor A
Vendor B
3.2x
2.5x 2.4x
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eGaN FET Loss Mechanisms
Like A MOSFET
• I²R Conduction Loss
• Capacitive Switching Losses
• Gate Drive Losses
• V×I Switching Loss
Not Like A MOSFET
• High Reverse Conduction Loss
• No Body Diode Reverse Recovery Loss
Can be much, much better than comparable silicon MOSFET
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Package Wish List
• Low parasitic resistance
• Low parasitic inductance
• Low thermal resistance
• Small size
• Low cost
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Flip-Chip LGA Construction
Printed Circuit Board
Copper Trace
eGaN FET Silicon Solder
Bar
Absolute minimum lead resistance and inductance!
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Gate
Substrate
Source Contacts
LGA Construction
Drain Contacts Interleaving to reduce layout
inductance
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Size Comparison – 200 V
D-PAK
eGaN FET
Drawn To Scale
5.76 mm²
65.3 mm²
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Design Basics
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Design Basics Agenda
• Requirements for: – Gate Driver – Dead-time – Layout – Paralleling – Thermal – Measurement
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Gate Drive
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Low VGS(on) Overhead
VGS(Max) = 6 V
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VGS eGaN FET
Minimizing Overshoot
80 ns/ div 2 V/ div
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eGaN FET Drive Requirements
• Minimize gate loop inductance
• Separate source and sink transistors allowing
for separate drive paths
To avoid overshoot:
GS
SGG
C
LLR
)(4
LS
RG(INT)
CGS
LGR
G(EXT)
RG
= RG(INT)
+ RG(EXT)
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VGS eGaN FET VGS eGaN FET
Minimizing Overshoot
20 ns/ div 1 V/ div
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eGaN FET Driver IC
• Bootstrap clamp limits (HS) supply
Reference: Texas Instruments, “Gate Drivers for Enhancement Mode GaN Power FETs 100 V Half-Bridge and
Low-Side Drivers Enable Greater Efficiency, Power Density, and Simplicity,” SNVB001
• Optimized drive impedance
• Separate inputs allow accurate, dead-time management
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Dead-time Requirements
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TDead
Cin
T
SR
Reverse Conduction Period
VGS_T
V VSW
t
VGS_SR
VSW
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MOSFET
eGaN FET
eGaN FET Reverse Conduction
+ Zero QRR
+ QRR
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TDead
VGS_T
V VSW
t
VGS_SR
Cin
T
SR
VSW
Reverse Conduction Period
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0
0.2
0.4
0.6
0.8
1
1.2
1.4
-5 0 5 10 15
Dead
-tim
e L
oss (
W)
Dead-Time (ns)
eGaN FET
Si MOSFET
w/o QRR
Impact of Dead-time
0
0.2
0.4
0.6
0.8
1
1.2
1.4
-5 0 5 10 15
Dead
-tim
e L
oss (
W)
Dead-Time (ns)
eGaN FET
Si MOSFET
w/o QRR
eGaN FET w/Schottky
VIN =12 V, VOUT =1.2 V, IOUT=20 A, and fsw =1 MHz
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82
83
84
85
86
87
88
89
90
2 4 6 8 10 12 14 16 18 20 22 24 26 28
Eff
icie
ncy (
%)
Output Current (A)
eGaN FET
TDEAD ≈ 2.5 ns
Si MOSFET
TDEAD ≈ 2.5 ns
w/o Schottky
82
83
84
85
86
87
88
89
90
2 4 6 8 10 12 14 16 18 20 22 24 26 28
Eff
icie
ncy (
%)
Output Current (A)
eGaN FET
TDEAD ≈ 2.5 ns
eGaN FET
TDEAD ≈ 5 ns
Si MOSFET
TDEAD ≈ 2.5 ns
w/o Schottky
82
83
84
85
86
87
88
89
90
2 4 6 8 10 12 14 16 18 20 22 24 26 28
Eff
icie
ncy (
%)
Output Current (A)
eGaN FET
TDEAD ≈ 2.5 ns
eGaN FET
TDEAD ≈ 10 ns
eGaN FET
TDEAD ≈ 5 ns
Si MOSFET
TDEAD ≈ 2.5 ns
w/o Schottky
82
83
84
85
86
87
88
89
90
2 4 6 8 10 12 14 16 18 20 22 24 26 28
Eff
icie
ncy (
%)
Output Current (A)
eGaN FET
TDEAD ≈ 2.5 ns
eGaN FET
TDEAD ≈ 10 ns
eGaN FET
TDEAD ≈ 5 ns
Si MOSFET
TDEAD ≈ 2.5 ns
w/o Schottky
w/ Schottky
VIN =12 V, VOUT =1.2 V, and fsw =1 MHz
Impact of Dead-time
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Fixed Dead-time Implementation
G N D
A
B
Y
V D D
U 1
NC7SZ00L6X
R 5
47.0
C 7
1 0 0 p
D 2
SDM03U40
R 4
22.0
C 6
1 0 0 p
D 1
SDM03U40
V C C
2
P 1
Optional
2
P 2
Optional
G N D
A
B
Y
V D D
U 4
NC7SZ08L6X
Used on all EPC90XX boards
Single PWM input
Inverter
Buffer
To LM5113 High side input To LM5113 Low side input
RCD filters delay turn-on, but not turn-off
Dead-time
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Layout
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tCF ∝ QGS2 tVR ∝ QGD
Ideal Hard Switching
VDS IDS
VGS
VIN
IOFF
𝐏𝐭𝐕𝐑 ≈𝐕𝐈𝐍 ∗ 𝐈𝐎𝐅𝐅 ∗ 𝐐𝐆𝐃
𝟐 ∗ 𝐈𝐆 𝐏𝐭𝐂𝐅 ≈
𝐕𝐈𝐍 ∗ 𝐈𝐎𝐅𝐅 ∗ 𝐐𝐆𝐒𝟐𝟐 ∗ 𝐈𝐆
t
VPL VTH
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0
10
20
30
40
50
60
70
80
100 V eGaN®FETGen2
100 V eGaN®FETGen 4
100 V MOSFET 1 100 V MOSFET 2 100 V MOSFET 3
FO
M =
(Q
GD+
QG
S2)*
RD
SO
N (p
C*Ω
)
QGD
QGD
QGD QGD QGD
QGS2
QGS2
QGS2
QGS2 QGS2
100 V Device Comparison
VDS=0.5*VDS, IDS= 10 A
100 V
eGaN FETs
100 V MOSFETs
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3
3.25
3.5
3.75
4
4.25
4.5
4.75
5
5.25
5.5
0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3P
ow
er
Lo
ss(W
)
Parasitic Inductance (nH)
Power Loss vs Parasitic Inductance
Ls
3
3.25
3.5
3.75
4
4.25
4.5
4.75
5
5.25
5.5
0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3P
ow
er
Lo
ss(W
)
Parasitic Inductance (nH)
Power Loss vs Parasitic Inductance
Ls LLoop
Cin
T
SR
LS: Common Source
Inductance VIN=12 V, VOUT=1.2 V,
fsw=1 MHz, IOUT= 20 A LLoop: High Frequency
Power Loop Inductance
Converter Parasitics
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LGA
0
0.5
1
1.5
2
2.5
SO-8 LFPAK DirectFET LGA
Po
we
r L
os
s (
W)
Device Loss Breakdown
Package
Die
18%
82%
0
0.5
1
1.5
2
2.5
SO-8 LFPAK DirectFET LGA
Po
we
r L
os
s (
W)
Device Loss Breakdown
Package
Die
18%
82%
27%
73%
0
0.5
1
1.5
2
2.5
SO-8 LFPAK DirectFET LGA
Po
we
r L
os
s (
W)
Device Loss Breakdown
Package
Die
18%
82%
27%
73%
53%
47%
0
0.5
1
1.5
2
2.5
SO-8 LFPAK DirectFET LGA
Po
we
r L
os
s (
W)
Device Loss Breakdown
Package
Die
18%
82%
27%
73%
53%
47%
82%
18%
LGA eGaN FET SO-8 LFPAK DirectFET
65
70
75
80
85
90
0.5 1 1.5 2 2.5 3 3.5
Eff
icie
ncy (
%)
Switching Frequency (MHz)
SO-8
LFPAK
DirectFET
LGA
VIN =12V
VOUT =1.2V
IOUT =20A
fsw =1MHz
Drain
Source
Gate
Package Impact on Efficiency
www.epc-co.com 59 EPC - The Leader in GaN Technology | September , 2014 |
83
84
85
86
87
88
89
90
91
2 4 6 8 10 12 14 16 18 20 22 24
Eff
icie
ncy (
%)
Output Current (A)
LLoop≈
1.0nH
40 V eGaN FET 40 V MOSFET
LLoop≈
2.2nH
83
84
85
86
87
88
89
90
91
2 4 6 8 10 12 14 16 18 20 22 24
Eff
icie
ncy (
%)
Output Current (A)
LLoop≈
1.0nH LLoop≈
1.7nH
40 V eGaN FET 40 V MOSFET
LLoop≈
2.2nH
83
84
85
86
87
88
89
90
91
2 4 6 8 10 12 14 16 18 20 22 24
Eff
icie
ncy (
%)
Output Current (A)
LLoop≈
1.0nH LLoop≈
1.7nH
LLoop≈
0.4nH
40 V eGaN FET 40 V MOSFET
LLoop≈
2.2nH
VIN=12 V, VOUT=1.2 V, fsw=1 MHz, L=300 nH
Measured Efficiency
Layout Impact on Efficiency
Ref: D. Reusch, J. Strydom,
“Understanding the Effect of PCB Layout
on Circuit Performance in a High
Frequency Gallium Nitride Based Point of
Load Converter,” APEC 2013
EPC Optimal Layout
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LLoop≈1.0 nH LLoop ≈ 0.4 nH
Layout Impact on Peak Voltage
VIN=12 V VOUT=1.2 V IOUT=20 A
fsw=1 MHz L=150 nH
Switching Node Voltage
70% Overshoot 30% Overshoot
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Top View
Conventional Lateral Layout
Side View
Shield Layer
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Top View Side View
Conventional Vertical Layout
Bottom View
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Side View
Top View
EPC Optimal Layout
Top View
Inner Layer 1
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CIN
Q1
Q2
U2
Optimal Layout Implementation
CIN
Q1
Q2
U2
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Layout Inductance Comparison
Top View Test Cases Board Thickness (mils)
Inner Layer Distance (mils)
Design 1 31 4 Design 2 31 12 Design 3 62 4 Design 4 62 26
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Power Loss Comparison
VIN=12 V VOUT=1.2 V IOUT=20 A fsw=1 MHz L=300 nH
T/SR: EPC2015 Driver LM5113
3
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9
4
0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
Po
wer
Lo
ss (
W)
High Frequency Loop Inductance (nH)
Vertical Power
Loop
Lateral Power
Loop
Optimal Power
Loop
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Efficiency Comparison
VIN=12 V VOUT=1.2 V fsw=1 MHz L=300 nH
GaN T/SR: EPC2015 Driver LM5113
83
84
85
86
87
88
89
90
91
2 4 6 8 10 12 14 16 18 20 22 24 26
Eff
icie
nc
y (
%)
Output Current (A)
40 V MOSFET
Vertical Design 1
Vertical
Design 1
Lateral
Design 1
Optimal
Design 1
40 V
eGaN FET
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Voltage Overshoot Comparison
VIN=12 V VOUT=1.2 V IOUT=20 A fsw=1 MHz L=300 nH
T/SR: EPC2015 Driver LM5113
20
30
40
50
60
70
80
90
100
0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
Vo
ltag
e O
vers
ho
ot
(%)
High Frequency Loop Inductance (nH)
Vertical Power
Loop
Lateral Power
Loop
Optimal Power
Loop
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Switching Speed Comparison
VIN=12 V VOUT=1.2 V IOUT=20 A fsw=1 MHz L=300 nH
T/SR: EPC2015 Driver LM5113
0
1
2
3
4
5
6
7
8
9
10
0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
eG
aN
FE
T d
V/d
t (V
/ns
)
High Frequency Loop Inductance (nH)
Vertical Power
Loop
Lateral Power
Loop
Optimal Power
Loop
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eGaN FET vs. MOSFET
VIN=12 V VOUT=1.2 V IOUT=20 A fsw=1 MHz L=300 nH eGaN FET
T/SR: EPC2015 MOSFET T:BSZ097N04 SR:BSZ040N04
Si MOSFET
eGaN FET
3 V/ div 20 ns/ div
www.epc-co.com 71 EPC - The Leader in GaN Technology | September , 2014 |
0
5
10
15
20
25
30
35
40V eGaN®FETGen 2
30V eGaN®FETGen 4
40 V MOSFET 1 40 V MOSFET 2 25V MOSFET 1 25V MOSFET 2
FO
M=
(QG
D+
QG
S2)*
RD
SO
N (p
C*Ω
)
QGD
QGD QGD
QGD QGD
QGS2
QGS2
QGS2
QGS2 QGS2
40 V MOSFETs
25 V MOSFETs 40 V
eGaN FET
QGD
QGS2
30 V
eGaN FET
Lower Voltage Comparison
www.epc-co.com 72 EPC - The Leader in GaN Technology | September , 2014 |
80
81
82
83
84
85
86
87
88
89
90
91
2 4 6 8 10 12 14 16 18 20 22
Eff
icie
ncy (
%)
Output Current (A)
40 V Discrete eGaN FET
40 V Discrete MOSFET
80
81
82
83
84
85
86
87
88
89
90
91
2 4 6 8 10 12 14 16 18 20 22
Eff
icie
ncy (
%)
Output Current (A)
40 V Discrete eGaN FET
40 V Discrete MOSFET
25 V Discrete MOSFET
80
81
82
83
84
85
86
87
88
89
90
91
2 4 6 8 10 12 14 16 18 20 22
Eff
icie
ncy (
%)
Output Current (A)
40 V Discrete eGaN FET
40 V Discrete MOSFET
25 V Discrete MOSFET
30 V Module MOSFET
VIN=12 V VOUT=1.2 V fsw=1 MHz L=300 nH
Lower Voltage Comparison
www.epc-co.com 73 EPC - The Leader in GaN Technology | September , 2014 |
40 V Si MOSFET
30 V Si MOSFET Module
VIN=12 V VOUT=1.2 V IOUT=20 A fsw=1 MHz L=300 nH
40 V
eGaN FET
3 V/Div 20 ns/ div
Switch Node Voltage
Switching Comparison
www.epc-co.com 74 EPC - The Leader in GaN Technology | September , 2014 |
EPC9107 Demonstration Board
VIN=12-28 V VOUT=3.3 V
IOUT=15 A fsw=1 MHz
2 x EPC2015
5 V/ div
Switching Node
Voltage VIN=28 V, IOUT=15 A
VIN=28 V ~3V overshoot @ 15 AOUT
20ns
~1.1ns rise time @ 15 A
www.epc-co.com 75 EPC - The Leader in GaN Technology | September , 2014 |
VIN=12 V VOUT=1.2 V
86
87
88
89
90
91
92
93
94
2 6 10 14 18 22 26 30 34 38 42 46 50
Eff
icie
nc
y (
%)
Output Current (A)
EPC2015 +
EPC2015
EPC2015 +
EPC2023
fsw=0.5 MHz
fsw=1 MHz
30 V
MOSFET
Module
Higher Current Devices
www.epc-co.com 76 EPC - The Leader in GaN Technology | September , 2014 |
0
1
2
3
4
5
6
7
8
9
10
2 6 10 14 18 22 26 30 34 38 42 46 50
Po
wer
Lo
ss
(W
)
Output Current (A)
EPC2015 +
EPC2015
EPC2015 +
EPC2023
fsw=0.5 MHz
fsw=1 MHz
30 V
MOSFET
Module
VIN=12 V VOUT=1.2 V
Higher Current Devices
www.epc-co.com 77 EPC - The Leader in GaN Technology | September , 2014 |
Paralleling High-Speed eGaN FETs
www.epc-co.com 78 EPC - The Leader in GaN Technology | September , 2014 |
Parallel Power Devices
?
www.epc-co.com 79 EPC - The Leader in GaN Technology | September , 2014 |
QGS2 QGD
VDS
t
VTH
Unbalanced Loop Inductance
VGS1
VGS2
IDS1
IDS2
IDS
VGS
VDS1
VDS2
www.epc-co.com 80 EPC - The Leader in GaN Technology | September , 2014 |
Loop Inductance Impact
0
5
10
15
20
25
30
35
40
45
0 0.2 0.4 0.6 0.8 1 1.2
Cu
rre
nt
Dif
fere
nc
e (
%)
Loop Inductance Difference (nH)
LS=0.10nH
LS=0.15nH
LS=0.20nH
LS=0.25nH
LS=0.50nH
VIN=48 V IOUT=25 A eGaN FET T/SR: 100 V EPC2001
www.epc-co.com 81 EPC - The Leader in GaN Technology | September , 2014 |
VIN=48 V VOUT=12 V IOUT=30 A fsw=300 kHz L=3.3 µH GaN FET T/SR: 100 V EPC2001
10 V/ div 5 ns/ div
SR1 SR4
Single Loop Optimal Layout
T1-4 SR1 SR4
www.epc-co.com 82 EPC - The Leader in GaN Technology | September , 2014 |
VIN=48 V VOUT=12 V IOUT=30 A fsw=300 kHz L=3.3 µH GaN FET T/SR: 100 V EPC2001
10 V/ div 5 ns/ div
SR1
SR4
T1
T2 T4
T3
SR2 SR4
SR3 SR1 SR4
Parallel Loop Optimal Layout
www.epc-co.com 83 EPC - The Leader in GaN Technology | September , 2014 |
94.5
95
95.5
96
96.5
97
2 6 10 14 18 22 26 30 34 38 42
Eff
icie
ncy (
%)
Output Current (A)
4 ǁ eGaN FETs
Proposed Four Distributed
Power Loops Design
Conventional Single
Power Loop Design
Parallel Layout Performance
VIN=48 V VOUT=12 V fsw=300 kHz L=3.3 µH GaN FET T/SR: 4x100 V EPC2001
4 Layer 2 oz PCB
www.epc-co.com 84 EPC - The Leader in GaN Technology | September , 2014 |
T1-4 SR1-4
Parallel Layout Implementation
T1
T2 T4
T3
SR1
SR2 SR4
SR3
VIN=48 V VOUT=12 V IOUT=30 A fsw=300 kHz L=3.3 µH GaN FET T/SR: 100 V EPC2001
www.epc-co.com 85 EPC - The Leader in GaN Technology | September , 2014 |
30
40
50
60
70
80
90
100
110
2 6 10 14 18 22 26 30 34 38
Maxim
um
Tem
pera
ture
(°C
)
Output Current (A)
Proposed Four Distributed
Power Loops Design
Conventional Single
Power Loop Design
Parallel Layout Performance
VIN=48 V VOUT=12 V fsw=300 kHz L=3.3 µH GaN FET T/SR: 100 V EPC2001
Fan Speed 200 LFM 4 Layer 2 oz PCB
www.epc-co.com 86 EPC - The Leader in GaN Technology | September , 2014 |
10 V/ div 5 ns/ div
2x eGaN FET
4x eGaN FET
1x eGaN FET
Parallel eGaN FET Swithcing
VIN=48 V VOUT=12 V IOUT=30 A/ number of devices fsw=300 kHz GaN FET T/SR: 100 V EPC2001
www.epc-co.com 87 EPC - The Leader in GaN Technology | September , 2014 |
92
92.5
93
93.5
94
94.5
95
95.5
96
96.5
97
97.5
98
98.5
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
Eff
icie
nc
y (
%)
Output Current (A)
300kHz
EPC2001 4 ǁ EPC2001
245 kHz Si
Isolated IBC
150 kHz Si
Isolated IBC
14 W
Parallel Buck in IBC Applications
VIN=48 V VOUT=12 V Fully Regulated IBC
92
92.5
93
93.5
94
94.5
95
95.5
96
96.5
97
97.5
98
98.5
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
Eff
icie
nc
y (
%)
Output Current (A)
300kHz
EPC2001 4 ǁ EPC2001
300kHz EPC2001 + EPC2021
245 kHz Si
Isolated IBC
150 kHz Si
Isolated IBC
14 W
www.epc-co.com 88 EPC - The Leader in GaN Technology | September , 2014 |
Higher Current Devices
VIN=48 V VOUT=12 V
92
93
94
95
96
97
98
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
Eff
icie
nc
y (
%)
Output Current (A)
fsw=300 kHz
fsw=500 kHz
80V MOSFET
80 V EPC
Gen 4
100 V EPC
Gen 2
www.epc-co.com 89 EPC - The Leader in GaN Technology | September , 2014 |
Higher Current Devices
VIN=48 V VOUT=12 V VIN=48 V VOUT=12 V
0
1
2
3
4
5
6
7
8
9
10
11
12
13
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
Po
wer
Lo
ss
(W
)
Output Current (A)
EPC2001
+
EPC2001
EPC2001
+
EPC2021
fsw=300 kHz
fsw=500 kHz
80V MOSFET
www.epc-co.com 90 EPC - The Leader in GaN Technology | September , 2014 |
Fan Speed=200 LFM fsw=300 kHz VIN=48 V VOUT=12 V IOUT=30 A
Improved Thermal Performance
www.epc-co.com 91 EPC - The Leader in GaN Technology | September , 2014 |
Thermal
www.epc-co.com 92 EPC - The Leader in GaN Technology | September , 2014 |
RƟCA
Thermal Management
Silicon Substrate
Active GaN Device Region RƟJC
RƟBA
RƟJB
TJ
www.epc-co.com 93 EPC - The Leader in GaN Technology | September , 2014 |
Packaging Advancements
Single Sided
Cooling
RƟJB ↓
www.epc-co.com 94 EPC - The Leader in GaN Technology | September , 2014 |
Package Comparisons
0
0.5
1
1.5
2
2.5
3
0 5 10 15 20 25 30 35
RƟ
JB
, Th
erm
al
Resis
tan
ce (
°C/W
)
Device Area (mm2)
RθJB_Si RθJB_GaN
www.epc-co.com 95 EPC - The Leader in GaN Technology | September , 2014 |
Package Comparisons
0
0.5
1
1.5
2
2.5
3
0 5 10 15 20 25 30 35
RƟ
JC
, T
herm
al
Re
sis
tan
ce (
°C/W
)
Device Area (mm2)
RθJC_Si RθJC_GaN
www.epc-co.com 96 EPC - The Leader in GaN Technology | September , 2014 |
80
81
82
83
84
85
86
87
88
89
90
91
2 4 6 8 10 12 14 16 18 20 22
Eff
icie
ncy (
%)
Output Current (A)
40 V eGaN FET
40 V MOSFET
Performance Comparison
VIN=12 V, VOUT=1.2 V, fsw=1 MHz, L=300 nH
www.epc-co.com 97 EPC - The Leader in GaN Technology | September , 2014 |
VIN=12 V, VOUT=1.2 V, IOUT=20 A, fsw=1 MHz, L=300 nH
Thermal Comparison
GaN is 38% Smaller 13% Cooler
www.epc-co.com 98 EPC - The Leader in GaN Technology | September , 2014 |
VIN=12 V, VOUT=1.2 V, fsw=1 MHz, L=300 nH
Thermal Comparison
20
30
40
50
60
70
80
90
100
110
120
130
140
150
2 4 6 8 10 12 14 16 18 20 22 24 26
Ma
xim
um
Te
mp
era
ture
(C
)
Output Current (A)
eGaN FET
MOSFET
0 LFM
20
30
40
50
60
70
80
90
100
110
120
130
140
150
2 4 6 8 10 12 14 16 18 20 22 24 26
Ma
xim
um
Te
mp
era
ture
(C
)
Output Current (A)
eGaN FET
MOSFET
0 LFM 200 LFM
www.epc-co.com 99 EPC - The Leader in GaN Technology | September , 2014 |
VIN=12 V VOUT=1.2 V
Generation 4 Thermal Performance
20
30
40
50
60
70
80
90
100
110
120
130
140
150
0 4 8 12 16 20 24 28 32 36 40 44
Ma
xim
um
Te
mp
era
ture
(°C
)
Output Current (A)
400 LFM
fsw=1 MHz
200 LFM
Natural
Convection
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Measurement
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Voltage Measurement
Place probe tip in large via or exposed pad
Minimize loop
Do not use probe ground lead
Do not let probe
tip touch the
low-side die!
Ground probe against TP3 OR use wire ground
www.epc-co.com 102 EPC - The Leader in GaN Technology | September , 2014 |
Probe Options
Yokogawa Probe Hand-made Probe Adapter
Tektronix PCB Jack
http://www.google.com/url?sa=i&source=images&cd=&cad=rja&docid=GxR4oJqSXMWk4M&tbnid=2KVfX9IRNlJiuM:&ved=0CAgQjRwwAA&url=http://www.cliftonlaboratories.com/july_2007.htm&ei=FknfUYzBBo2ujAKrmoCgAQ&psig=AFQjCNGu7o7kD8KZOEeXg1-zqyB2cmeBzg&ust=1373674134182653http://www.google.com/url?sa=i&source=images&cd=&cad=rja&docid=CkJfEDDyObddFM&tbnid=6OVVWJeJtOef0M:&ved=0CAgQjRwwADixAg&url=http://tmi.yokogawa.com/us/products/oscilloscopes/voltage-probes/pba2500-701913-25-ghz-active-probe/&ei=nknfUZWrMMmsiQLBqIH4Ag&psig=AFQjCNFExzkwIwq3rXy3Ifuk3UTpcvnaxg&ust=1373674270848600
www.epc-co.com 103 EPC - The Leader in GaN Technology | September , 2014 |
1GHz, 100:1, 1pF / 5k probe
4GHz, 40Gsa/s oscilloscope
500MHz, 10:1, 10pF / 10M probes
1GHz, 4Gsa/s oscilloscope
High Speed Measurement
www.epc-co.com 104 EPC - The Leader in GaN Technology | September , 2014 |
• eGaN FETs raise the bar for power conversion performance
• Lower resistance per die area
• Better FOM’s
• Better Packaging
• Improved PCB Layout Techniques
• Superior In-Circuit Performance
• Can parallel devices for higher current
• Avoid gate overshoot and long dead-times
Design Basics Summary
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Design Examples
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Design Example Agenda
• Resonant Bus Converter
• Envelope Tracking
• Wireless Power
• LiDAR
• Class-D Audio
www.epc-co.com 107 EPC - The Leader in GaN Technology | September , 2014 |
Resonant Bus Converter
www.epc-co.com 108 EPC - The Leader in GaN Technology | September , 2014 |
Figure of Merit (FOM) History
•In 1989, Baliga derived a switching FOM
•𝐁𝐇𝐅𝐅𝐎𝐌 =𝟏
𝐑𝐎𝐍,𝐒𝐏∙𝐂𝐈𝐍,𝐒𝐏
•In 1995, Kim et al proposed a new FOM
•𝐍𝐇𝐅𝐅𝐎𝐌 =𝟏
𝐑𝐎𝐍,𝐒𝐏∙𝐂𝐎𝐒𝐒,𝐒𝐏
•In 2004, Huang proposed a new FOM
•𝐇𝐃𝐅𝐎𝐌 = 𝐑𝐎𝐍,𝐒𝐏 ∙ 𝐐𝐆𝐃,𝐒𝐏
www.epc-co.com 109 EPC - The Leader in GaN Technology | September , 2014 |
LM
Resonant Bus Converter
Ref: Y. Ren, M. Xu, J. Sun, and F. C. Lee, “A family of high power density unregulated bus converters,” IEEE Trans. Power Electron., vol. 20, no. 5, pp. 1045–1054, Sep. 2005.
High Frequency DC/DC Transformer
4:1
48V
VIN
+
-
Q1
Q2 Q3
Q4
CO
S2
S1
LK2
LK1
IPRIM
ILK1
VGS(Q2,Q4) VGS(S2)
VGS(Q1,Q3) VGS(S1)
VDS(Q1)
t0 t1
VIN
t2 t3
I Lk1
D
tZVS
ILM
IPRIM
www.epc-co.com 110 EPC - The Leader in GaN Technology | September , 2014 |
Gate Charge Figure of Merit
0
100
200
300
400
500
600
0 50 100 150 200 250
FO
M=
QG·R
DS
(on
) (p
C·Ω
)
Drain-to-Source Voltage (V)
EPC Gen 4
EPC Gen 2
Vendor A
Vendor B
Vendor C
Vendor D
Vendor E
9.9x
1.3x
4.2x
www.epc-co.com 111 EPC - The Leader in GaN Technology | September , 2014 |
𝑡𝑍𝑉𝑆
I
𝑡
Output Charge
sDRG fVQ =PG
V
𝑡
𝑉𝐷𝑆 𝑡𝑍𝑉𝑆
𝑉𝐺𝑆
QOSS
𝐼𝑆𝑊
tZVS IRMS PCON
𝐷 ∗ 𝑇𝑆
www.epc-co.com 112 EPC - The Leader in GaN Technology | September , 2014 |
VDS=0.5·VDSS
Output Charge FOM
0
200
400
600
800
1000
1200
1400
1600
0 50 100 150 200 250
FO
M=
QO
SS·R
DS
(on
) (p
C·Ω
)
Drain-to-Source Voltage (V)
EPC Gen 4
EPC Gen 2
Vendor A
Vendor B
2.6x
1.9x 1.7x
www.epc-co.com 113 EPC - The Leader in GaN Technology | September , 2014 |
0
100
200
300
400
500
600
700
800
0 50 100 150 200 250
FO
M=
QG\Q
OS
S·R
DS
(on
) (p
C·Ω
)
Drain-to-Source Voltage (V)
Soft-Switching FOM
QOSS
QG
𝐅𝐎𝐌𝐒𝐒 = (𝐐𝐎𝐒𝐒+𝐐𝐆) ∙ 𝐑𝐃𝐒(𝐨𝐧)
8x
3.5x 1.2x
www.epc-co.com 114 EPC - The Leader in GaN Technology | September , 2014 |
Soft-Switching FOM
𝐅𝐎𝐌𝐒𝐒 = (𝐐𝐎𝐒𝐒+𝐐𝐆) ∙ 𝐑𝐃𝐒(𝐨𝐧)
0
500
1000
1500
2000
2500
0 50 100 150 200 250
FO
MS
S=
(QG+
QO
SS)·
RD
S(o
n) (p
C·Ω
)
Drain-to-Source Voltage (V)
EPC Gen 4
EPC Gen 2
Vendor A
Vendor B
3.2x
2.5x 2.4x
www.epc-co.com 115 EPC - The Leader in GaN Technology | September , 2014 |
Transformer
Secondary
Devices
Primary
Devices
Input
Capacitors
Resonant
Capacitors
MOSFET vs. eGaN®FET
eGaN FET vs. MOSFET
www.epc-co.com 116 EPC - The Leader in GaN Technology | September , 2014 |
MOSFET VGS MOSFET VDS
eGaN FET VDS
eGaN FET VGS
fsw = 1.2 MHz, VIN = 48 V, and VOUT ≈ 12 V
TZVS = 87 ns
TZVS = 42 ns
ZVS Switching Comparison
www.epc-co.com 117 EPC - The Leader in GaN Technology | September , 2014 |
MOSFET VGS
MOSFET VDS
DMOSFET = 34% eGaN FET VDS
eGaN FET VGS
DeGaN FET = 42%
Duty Cycle Comparison
fsw = 1.2 MHz, VIN = 48 V, and VOUT ≈ 12 V
www.epc-co.com 118 EPC - The Leader in GaN Technology | September , 2014 |
90
91
92
93
94
95
96
97
98
0 5 10 15 20 25 30 35 40
Eff
icie
nc
y (
%)
Output Current (A)
1.2 MHz MOSFET
1.2 MHz eGaN FET
10 W 12 W
14 W
2
4
6
8
10
12
14
16
18
20
22
24
0 5 10 15 20 25 30 35 40
Po
wer
Lo
ss
(W
)
Output Current (A)
1.2 MHz eGaN FET
1.2 MHz MOSFET
5 A
Efficiency Comparison
fsw = 1.2 MHz, VIN = 48 V, and VOUT ≈ 12 V
www.epc-co.com 119 EPC - The Leader in GaN Technology | September , 2014 |
LK2
**
*
VIN-
VIN+ VOUT+
LIN
CIN
LK1
4:1
LOUT
COUTCRES
Q1
Q2 Q4
Q3
VOUT-
Q6,Q7
Q5,Q8
2 SR
2 SR
EPC9105 Demonstration Board 36 - 60 VIN, 12 VOUT, 350 W, 1.2 MHz
EPC9105 Bus Converter
www.epc-co.com 120 EPC - The Leader in GaN Technology | September , 2014 |
Envelope Tracking
www.epc-co.com 121 EPC - The Leader in GaN Technology | September , 2014 |
Same average
Reference: Nujira.com website
0
2
4
6
8
10
12
2012 2013 2014 2015 2016 2017
Ex
ab
yte
s p
er
Mo
nth
Source: Cisco VNI Mobile Data Traffic Forecast
66% Compound annual growth
rate (CAGR)
Why Envelope Tracking?
www.epc-co.com 122 EPC - The Leader in GaN Technology | September , 2014 |
Output Power (dBm)
Average
Power
Output
Probability
Envelope
Tracking
Fixed
supply
Peak Power
PAPR = 0dB
Peak efficiency
up to 65%
Envelope Tracking
www.epc-co.com 123 EPC - The Leader in GaN Technology | September , 2014 |
Gen 3 FOM
EPC2014
EPC8004
eGaN FET
EPC8000 Series
www.epc-co.com 124 EPC - The Leader in GaN Technology | September , 2014 |
Hard Switching FOM
www.epc-co.com 125 EPC - The Leader in GaN Technology | September , 2014 |
HB Layout – Top Layer
To BUS caps
Switch
node
Ground Bottom Gate
Top Gate Ga
te
Drain
Source
Sub
S
Gate
Drain Sub
S
Re
turn
R
etu
rn
Source
Gate
Current
orthogonal
to drain
current
Vias to next layer
Supply
Vias to next layer
www.epc-co.com 126 EPC - The Leader in GaN Technology | September , 2014 |
Optimum gate
loop return
Optimum gate
loop return
To gate
drive
To gate
drive
Optimum power
loop return
Gate
Drain
Source
Sub
S
Gate
Drain Sub
S
Re
turn
R
etu
rn
Source
HB Layout – Inner Layer 1
www.epc-co.com 127 EPC - The Leader in GaN Technology | September , 2014 |
Envelope Tracking Prototype Board
EPC8005
Bus caps
SO-8 footprint
EPC8005 LM5113
www.epc-co.com 128 EPC - The Leader in GaN Technology | September , 2014 |
VIN=42 V VOUT=20 V
65%
70%
75%
80%
85%
90%
95%
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
Eff
icie
nc
y
Output Current (A)
5 MHz
10 MHz EPC8005
High Frequency Efficiency
www.epc-co.com 129 EPC - The Leader in GaN Technology | September , 2014 |
EPC8005
42VIN, 10 MHz Losses
Conduction
Switching
COSS
Unaccounted losses
www.epc-co.com 130 EPC - The Leader in GaN Technology | September , 2014 |
10 MHz switching, no load, large dead-time
No-Load Switching
Initially slow
rising edge
Actual voltage commutation
slopes are different, even
though currents are the same
10V/div, 100mA/div, 10ns/div
Expected commutation based on
eGaN FET COSS
www.epc-co.com 131 EPC - The Leader in GaN Technology | September , 2014 |
Le
ve
l S
hift
VDD VDD
IC c
ap
acita
nce
Bo
ots
tra
p d
iod
e
Reverse
recovery
charge
Switch-node
rising edge
LM5113 half-bridge
driver
Parasitic Losses
www.epc-co.com 132 EPC - The Leader in GaN Technology | September , 2014 |
Bootstrap QRR
10 MHz switching, no load, large dead-time 10V/div, 100mA/div, 10ns/div
Switch-node voltage
Actual commutation based on total
COSS – including IC capacitance
Loss Breakdown
www.epc-co.com 133 EPC - The Leader in GaN Technology | September , 2014 |
EPC8005
Conduction
Switching
COSS
Unaccounted losses
42VIN, 10 MHz Losses
www.epc-co.com 134 EPC - The Leader in GaN Technology | September , 2014 |
Calculated efficiency improvement
eGaN FET Limited Efficiency
www.epc-co.com 135 EPC - The Leader in GaN Technology | September , 2014 |
Wireless Power
www.epc-co.com 136 EPC - The Leader in GaN Technology | September , 2014 |
Wireless Power
• The global wireless charging market is estimated to grow to $10B by
2018, a CAGR of 42.6%
• eGaN FETs enable higher efficiency and operation at safer
frequencies
www.epc-co.com 137 EPC - The Leader in GaN Technology | September , 2014 |
Experimental System Setup
eGaN FETs RF connection
Device Board
Source Coil Source Board
Coil Feedback
Device Coil
25m
m
RF connection
50mm
www.epc-co.com 138 EPC - The Leader in GaN Technology | September , 2014 |
Coil Simplification
Lsrc Ldev
Cdevs
RDCload
Cout
Ldevs
Cdevp Zload
Coil Set
Simplified representation of coil-set for easy comparison between topologies
www.epc-co.com 139 EPC - The Leader in GaN Technology | September , 2014 |
Single Ended Class-E
VDD
Ideal Waveforms
VDS ID
time
3.56 x VDD
V / I
50%
Q1
+
Csh
Cs Le LRFck
Zload
• Switch voltage rating ≥ 3.56·Supply (VDD).
• COSS “absorbed” into matching network.
• Susceptible to load variation - high FET losses.
• Coil voltage ≈ 0.707·VDD [VRMS].
www.epc-co.com 140 EPC - The Leader in GaN Technology | September , 2014 |
Class-E Device Comparison
FoMWPT [nC·mΩ]
0
200
400
600
800
1000
1200
1400
1600
EPC
20
12
MO
SFET
SE-CE
SE-CE
GDGDS(on)WPT QQRFOM
100
200
300
400
500
600
700
800
900
1000
0 100 200 300 400 500 600
Devic
e P
ow
er
[mW
]
RDS(on) [mΩ]
MOSFET
eGaN FET
Gate Power
dominant
Conduction Loss
dominant
Lowest Power Dissipation
www.epc-co.com 141 EPC - The Leader in GaN Technology | September , 2014 |
Class-E Analysis Comparison
2
6
10
14
18
80
85
90
95
100
0 10 20 30 40 50
Ou
tpu
t P
ow
er
[W]
Effi
cie
ncy
[%
]
DC Load Resistance [Ω]
eGaN FET Eff.
MOSFET Eff.
eGaN FET Pout
MOSFET Pout
EPC2012
MOSFET 95.6%
98.5 %
85.2%
94.4%
Peak Power Device losses = 279 mW No Heat-Sink Required
www.epc-co.com 142 EPC - The Leader in GaN Technology | September , 2014 |
ZVS Class-D
+ VDD
Cs Q2
Q1 Zload
LZVS
CZVS
V / I
VDS ID
time
VDD
50%
Ideal Waveforms ZVS tank
• Switch voltage rating = Supply (VDD).
• COSS voltage is transitioned by the ZVS tank .
• ZVS tank circuit does not carry load current.
• Coil voltage = ½·VDD [VRMS].
www.epc-co.com 143 EPC - The Leader in GaN Technology | September , 2014 |
Device Comparison
020406080
100120140160180
EP
C8009
EP
C2007
MO
SF
ET
2
MO
SF
ET
3
ZVS-CD
FoM
WP
T [
nC
·mΩ
]
VG
S =
10
V
GDGDS(on)WPT QQRFOM
ZVS-CD
www.epc-co.com 144 EPC - The Leader in GaN Technology | September , 2014 |
64
68
72
76
80
84
10 15 20 25 30 35 40 45 50
Eff
icie
ncy [
%]
DC Load Resistance [Ω]
64
68
72
76
80
84
10 15 20 25 30 35 40 45 50
Eff
icie
ncy [
%]
DC Load Resistance [Ω]
Load Variation Results
η EPC8009 ZVS-CD
η MOSFET 2 ZVS-CD
η MOSFET 3 ZVS-CD η EPC2012 SE-CE
η MOSFET 1 SE-CE
Coil becomes Inductive
Coil becomes Capacitive
Fixed Supply Voltage
www.epc-co.com 145 EPC - The Leader in GaN Technology | September , 2014 |
LiDAR
www.epc-co.com 146 EPC - The Leader in GaN Technology | September , 2014 |
LIght Detection And Ranging
• Autonomous vehicles • Video games • Geology • Agriculture
http://www.usgs.gov/blogs/features/usgs_top_story/hurricane-season-is-here/
www.epc-co.com 147 EPC - The Leader in GaN Technology | September , 2014 |
LiDAR
Courtesy of OmniPulse
www.epc-co.com 148 EPC - The Leader in GaN Technology | September , 2014 |
Class-D Audio
www.epc-co.com 149 EPC - The Leader in GaN Technology | September , 2014 |
Why eGaN FETs in Class-D Audio
• Low RDS(on) & Low COSS + High Efficiency
+ High Damping Factor = Low open loop output Impedance = Low T-IMD
• Fast Switching & No Reverse Recovery (Qrr) + High output linearity, Low
Cross-over Distortion
= Low THD
www.epc-co.com 150 EPC - The Leader in GaN Technology | September , 2014 |
eGaN FET Class-D Audio Amplifier
RCA Inputs
XLR Input
XLR Input
±30 V supply
Speaker Connections
• Bridge-Tied-Load (BTL) • EPC2016 with LM5113
LF1
CF1Q2
Q1 LF2
Q4
Q3
CF2
eGaN FET Power Stage:
250 W into 4 Ω at 440 kHz without a heatsink
www.epc-co.com 151 EPC - The Leader in GaN Technology | September , 2014 |
A Look Into the Future
www.epc-co.com 152 EPC - The Leader in GaN Technology | September , 2014 |
Breaking Down the Barriers
• Does it enable significant new capabilities?
• Is it easy to use?
• Is it VERY cost effective to the user?
• Is it reliable?
www.epc-co.com 153 EPC - The Leader in GaN Technology | September , 2014 |
• Does it enable significant new capabilities?
• Is it easy to use?
• Is it VERY cost effective to the user?
• Is it reliable?
Breaking Down the Barriers
www.epc-co.com 154 EPC - The Leader in GaN Technology | September , 2014 |
Faster Transistors
eGaN FETs are Faster
Faster transistors enable the systems to get
smaller, more efficient, and lower cost.
www.epc-co.com 155 EPC - The Leader in GaN Technology | September , 2014 |
Key Applications
• Wireless Power Transmission
• RF DC-DC “Envelope Tracking”
• LiDAR
• RadHard
• Network and Server Power Supplies
• Point of Load Modules
• Energy Efficient Lighting
• Class D Audio
• Various Medical
www.epc-co.com 156 EPC - The Leader in GaN Technology | September , 2014 |
Product Revenue Forecast 2018
NRE 1%
Lighting 1%
RadHard 1% MRI 2%
Audio 2%
DC-DC 9% LiDAR 6%
WiPo 18%
Envelope Tracking 22%
AC-DC 38%
www.epc-co.com 157 EPC - The Leader in GaN Technology | September , 2014 |
• Does it enable significant new capabilities?
• Is it easy to use?
• Is it VERY cost effective to the user?
• Is it reliable?
Breaking Down the Barriers
www.epc-co.com 158 EPC - The Leader in GaN Technology | September , 2014 |
It’s just like a MOSFET
Is an eGaN FET Easy to Use?
except
The high frequency capability makes circuits using eGaN FETs sensitive to layout
The lower VG(MAX) of 6 V makes it advisable to have VGS regulation in your gate drive circuitry
www.epc-co.com 159 EPC - The Leader in GaN Technology | September , 2014 |
Educating
www.epc-co.com 160 EPC - The Leader in GaN Technology | September , 2014 |
• Virginia Tech • University of California at Santa Barbara • Rensselaer Polytechnic Institute • Hong Kong University of Science and Technology • Cornell University • Katholieke Universiteit Leuven • University of Bristol • University of Glasgow • University of Sheffield • University of Warsaw • University of Sydney • Massachusetts Institute of Technology • Cambridge University • National Central University of Taiwan • National Taiwan University • Chang Gung University • University of Florida • Florida State University • Case Western University
• Yale University • University of Ohio, Toledo • Ohio State University • Kyushu Institute of Technology • National Chiao Tung University • University of Tennessee • Auburn University • University of Texas • Yamaguchi University • Universitat Kassel • National Tsinghua University • Mid Sweden University • New Mexico State University • University of Johannesburg • University of Toronto • Universita di Padova • Delft University of Technology • Missouri University of Science and Technology • University of Maryland • Insitituto Italiano di Technologia
Universities all over the world are graduating well-trained engineers experienced in the use of GaN Transistors
Universities with GaN Transistor Programs
www.epc-co.com 161 EPC - The Leader in GaN Technology | September , 2014 |
92.5
93
93.5
94
94.5
95
95.5
96
96.5
97
0 1 2 3 4 5 6 7 8 9 10 11 12 13
Eff
icie
nc
y (
%)
Output Current (A)
DrGaNPLUS
300kHz
80V MOSFET
300kHz
92.5
93
93.5
94
94.5
95
95.5
96
96.5
97
0 1 2 3 4 5 6 7 8 9 10 11 12 13
Eff
icie
nc
y (
%)
Output Current (A)
DrGaNPLUS
300kHz
80V MOSFET
300kHz
DrGaNPLUS
500kHz
Simplifying GaN- DrGaNPLUS
VIN=48 V VOUT=12 V fsw=300 kHz L=10 µH eGaN FET T/SR: 100 V EPC2001
MOSFET T/SR: 80 V BSZ123N08NS3G
www.epc-co.com 162 EPC - The Leader in GaN Technology | September , 2014 |
Breaking Down the Barriers
• Does it enable significant new capabilities?
• Is it easy to use?
• Is it VERY cost effective to the user?
• Is it reliable?
www.epc-co.com 163 EPC - The Leader in GaN Technology | September , 2014 |
Silicon vs. eGaN Product Costs
Starting Material
Epi Growth
Wafer Fab
Test
Assembly
OVERALL
2014 2015
lower lower
higher
same
same
lower
lower
same
lower
~same?
lower! higher
www.epc-co.com 164 EPC - The Leader in GaN Technology | September , 2014 |
Breaking Down the Barriers
• Does it enable significant new capabilities?
• Is it easy to use?
• Is it VERY cost effective to the user?
• Is it reliable?
www.epc-co.com 165 EPC - The Leader in GaN Technology | September , 2014 |
High Temp Reverse Bias (HTRB)
Part Number Stress VDS (V) Temperature (oC) Sample Size
Results (# of fails)
Duration (Hrs)
EPC2001 80 150 207 0 500
EPC2001 80 150 144 0 168
EPC2001 80 150 80 0 1000
EPC2001 80 125 96 0 168
EPC2001 100 125 45 0 1000
EPC2016 80 150 239 0 500
EPC2016 100 150 80 0 168
• Over 0.5 million accumulated device hours of reliability testing without
failure across 891 devices.
www.epc-co.com 166 EPC - The Leader in GaN Technology | September , 2014 |
100 V HTRB Acceleration
90 °C
35 °C
150 °C
FIT Rate vs VDS and Temperature
0.0001%
1%0.01%
20 yrs
10 yrs
Tim
e to
Fai
l
www.epc-co.com 167 EPC - The Leader in GaN Technology | September , 2014 |
HTGB Acceleration
10 yrs
MTTF vs VGS
1 FIT
FIT Rate vs VGS
www.epc-co.com 168 EPC - The Leader in GaN Technology | September , 2014 |
High Temp Gate Bias (HTGB)
Part Number Stress VGS (V) Temperature (oC) Sample Size Results (# of fails) Duration (Hrs)
EPC2001 5 150 48 0 168
EPC2001 5 125 167 0 168
EPC2001 5 150 192 0 500
EPC2001 5 150 125 0 1000
EPC2014 5 150 48 0 500
EPC2015 5 125 96 0 168
EPC2015 5 150 50 0 1000
EPC2001 5.5 150 48 0 168
EPC2001 5.5 150 208 0 500
EPC2016 5.5 150 80 0 168
EPC2016 5.5 150 80 0 500
EPC2001 5.75 150 96 0 168
EPC2001 5.75 125 32 0 168
EPC2001 5.75 125 48 0 181
EPC2001 5.75 125 64 0 200
EPC2001 5.75 150 240 0 500
EPC2001 5.75 125 32 0 500
EPC2016 5.75 90 32 0 200
EPC2016 5.75 150 32 0 350
EPC2016 5.75 150 240 0 500
EPC2019 5.75 150 160 0 168
EPC2001 6 125 24 0 181
EPC2001 6 150 32 0 200
EPC2001 6 150 80 0 437
EPC2001 6 150 32 0 500
EPC2001 6 125 32 0 500
EPC2016 6 90 32 0 200
EPC2016 6 150 32 0 350
EPC2001 6.3 150 32 0 200
EPC2016 6.3 150 32 0 200
EPC2016 6.3 90 32 0 200
EPC2016 6.6 150 32 0 200
• 0 fail in over 0.97 million
accumulated device
hours of HTGB reliability
testing greater than 5V.
• 0 fail in over 0.6 million
accumulated device
hours of HTGB reliability
testing greater than
5.5V.
www.epc-co.com 169 EPC - The Leader in GaN Technology | September , 2014 |
A Look Into the Future
www.epc-co.com 170 EPC - The Leader in GaN Technology | September , 2014 |
Gen 2
2010-2013
40 V - 200 V
Generation 5
~December 2014
Moore’s Law Revival
Generation 3
Higher Frequency
Launched September 2013
High Voltage
September 2014
Half Bridge ICs
September 2014
Generation 4
2 X Performance Improvement
Launched June 2014
www.epc-co.com 171 EPC - The Leader in GaN Technology | September , 2014 |
Generation 2/4
Discrete HB
Generation 4
Monolithic 4:1 HB
+
GaN Integration
T
SR
Top Switch (T) Synchronous
Rectifier (SR) 33 % die size reduction
www.epc-co.com 172 EPC - The Leader in GaN Technology | September , 2014 |
Monolithic Half Bridge
70
72
74
76
78
80
82
84
86
88
90
2 6 10 14 18 22 26 30 34 38 42
Eff
icie
ncy (
%)
Output Current (A)
GaN POL
w/ Gen 4
Discrete Transistors
GaN POL
w/ Gen 4
Monolithic HB 33 % die size reduction
fsw=2 MHz fsw=4 MHz fsw=3 MHz
VIN=12 V VOUT=1.2 V L=100 nH
www.epc-co.com 173 EPC - The Leader in GaN Technology | September , 2014 |
Summary
• GaN transistors enable exciting new applications such as LiDAR, RF Envelope Tracking and Wireless Power Transmission
• GaN transistors have the potential to replace silicon power MOSFETs and LDMOS in power conversion applications with a low-cost and higher efficiency solution
• GaN technology is keeping Moore’s Law alive!