Application Note 900V CoolMOS™ C3

Application Note, V1.3, May 2008
CoolMOS TM 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy
applications
Power Management & Supply
Edition 2008-05-13
Published by
Infineon Technologies AG
81726 Munich, Germany
© 2008 Infineon Technologies AG
All Rights Reserved.
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CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
CoolMOSTM 900V
Revision History:
2008-05
Previous Version:
V1.1
03.04.2008
Modified chapter 3.2
13.05.2008
Disclaimer+Fig. 9 actual.
V1.3
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Application Note
3
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
Table of Contents
Page
1
1.1
Introduction...............................................................................................................................................5
The Superjunction Principle ........................................................................................................................6
2
Device characteristics..............................................................................................................................8
3
3.1
3.2
3.3
3.4
Target applications CoolMOSTM 900V ...................................................................................................10
Wide range designs (90…270Vac) with their typical 400Vdc bulk voltage ................................................10
Replacement of IGBTs by CoolMOS™ 900V Series.................................................................................14
Lighting applications .................................................................................................................................15
Auxiliary power supplies in 3-phase systems............................................................................................15
4
Product Portfolio ....................................................................................................................................16
5
5.1
5.2
5.3
5.4
5.5
Circuit Design and Layout Recommendations.....................................................................................17
Control dv/dt and di/dt by Proper Selection of Gate Resistor ....................................................................17
Minimize Parasitic Gate-Drain Board Capacitance ...................................................................................17
Locate Gate Drivers and Gate Turn-Off Components as Close as Possible to the Gate...........................18
Use Symmetrical Layout for Paralleling MOSFETs, and Good Isolation of Gate Drive between FETs .....18
Summary ..................................................................................................................................................18
References ........................................................................................................................................................19
Application Note
4
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
1
Introduction
Infineon introduces a new 900V voltage class of energy-saving CoolMOS
switch-mode power supply and renewable energy applications.
TM
power MOSFETs for high efficiency
TM
CoolMOS 900V offers extremely low static and dynamic losses, which is the signature of super junction
MOSFET technology where the so-called “silicon limit” is overcome. The square-law dependency between onresistance and blocking voltage in conventional MOSFETs is amended by new CoolMOSTM 900V, resulting in
an industry-best on-state resistance per package type being four times or even lower if compared to
conventional 900V MOSFETs: 0.12 Ohm in TO247, 0.34 Ohm in TO220, and 1.2 Ohm in DPAK packages. A
figure-of-merit (FOM) on-resistance times gate charge (RDSon*QG) as low as 34 Ω*nC is reached, which
translates into extremely low conduction, driving and switching losses.
Samples are available now and the complete product spectrum will be filled up during 2008.
Target applications for CoolMOSTM 900V are ATX power supplies, solar converters, quasiresonant flyback
designs for LCD TV, active frontend 3-phase-systems and other designs, were high blocking voltage, low
conduction and switching losses combined with low gate charge are necessary.
Table 1 gives a quick overview of available CoolMOSTM series today.
Table 1
CoolMOSTM Series at a Glance
Market
Entry
Voltage
Class [V]
Special
Characteristic
CoolMOSTM S5
1998
600
Low RDS(on), Switching speed
close to standard MOSFETs
CoolMOSTM C3
2001
500/600/
650/800
CoolMOSTM CFD
2004
CoolMOSTM CP
CoolMOSTM C3
Application Note
Vgs,th
Gfs
[V]
[S]
Internal Rg
[Ω]
4.5
Low
High
Fast switching speed
symmetrical rise/fall time
at VGS=10 V
3
High
Low
600
Fast body diode,
Qrr 1/10th of C3 series
4
High
Low
2005
500/600
Ultra-low RDS(on),
ultra-low Qg,
very fast switching speed
3
High
Low
2008
900
low RDS(on),
low Qg,
fast switching speed
3
High
Low
5
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
1.1
The Superjunction Principle
CoolMOSTM is a revolutionary technology for high voltage power MOSFETs and designed according to the
superjunction (SJ) principle [1], which in turn is based on the RESURF [2] ideas being successfully used for
decades in lateral power MOSFETs. Conventional power MOSFETs suffer from the limitation of the so-called
“silicon limit” [3], which means that doubling the voltage blocking capability typically leads to an increase in the
on-state resistance by a factor of five. The “silicon limit” is shown in Figure 1 where the area specific on-state
resistance of state-of-the-art standard MOSFETs as well are indicated. SJ technology may lower the on-state
resistance of a power MOSFET virtually towards zero. The basic idea is to allow the current to flow from top to
bottom of the MOSFET in very high doped vertically arranged regions. In other words, a lot more charge is
available for current conduction compared to what is the case in a standard MOSFET structure. In the blocking
state of the SJ MOSFET, the charge is counterbalanced by exactly the same amount of charge of the opposite
type. The two charges are separated locally in the device by a very refined technology, and the resulting
structure shows a laterally stacked fine-pitched pattern of alternating arranged p- and n-areas, see Figure 2.
The finer the pitch can be made, the lower the on-state resistance of the device will be.
Area specific resistance [Ohm*mm2]
40
30
20
State-of-the-art
conventional MOS
10
"Silicon Limit"
CoolMOSTM
0
500
Figure 1
600
700
800
Blocking voltage [V]
1000
Area-specific on-resistance versus breakdown voltage comparison of standard MOSFET
TM
and CoolMOS Technology
S
G
G
S
n
p+
pp
n+sub
D
-
- -
n epi
-
-
D
Standard MOSFET
Figure 2
900
Superjunction MOSFET
Schematic Cross-Section of a Standard Power MOSFET versus a Superjunction MOSFET
Application Note
6
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
Another signature of SJ technology is the extremely fast switching speed. The turn off behavior of a
SJ MOSFET is not characterized by the relatively slow voltage driven vertical expansion of the space charge
layer but by a sudden nearly intrinsic depletion of the laterally stacked p-n structure. This unique behavior
makes the device very fast. The neutralization of these depletion layers is done via the MOS controlled turn-on
of the load current for the n-areas and via a voltage driven drift current for the p-areas. SJ devices reach
therefore theoretical rise and fall times in the range of few nanoseconds.
Figure 3 shows a comparison of RDS(on),max between today’s most advanced available MOSFETs.
1.4
1.3
Best in Class TO-220 CoolMOS Infineon
1.2
Best in Class TO-220 Superjunction Competitor
Best in Class TO-220 Standard Technology Competitor
RDS(on) [Ohm]
1
0.75
0.8
0.6
0.5
0.43
0.4
0.4
0.27
0.23
0.2
0.14 0.14
0.34
0.29
0.19
0.099
0.13
0
500V
Figure 3
600V
650V
800V
900V
Comparison of RDS(on),max for most advanced MOSFETs in TO220 package available in the
market.
Application Note
7
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
2
Device characteristics
CoolMOSTM 900V is the next step towards THE IDEAL HIGH VOLTAGE SWITCH with key features:
✓
Very low conduction and switching losses
✓
Lowest on-state-resistance per package @ 900 V blocking capability
✓
Ultra-low gate charge and lowest figure-of-merit RDS(on) x Qg
… which gives the application benefits:
✓
Extremely reduced heat generation
✓
Reduced system size and weight
✓
Very low gate drive power facilitating the use of low cost ICs and gate drivers
✓
Reduced overall system cost
The most interesting circuit design aspect is that the more than square-law dependency of the area-specific onresistance (RDS(on) x A) on the breakdown voltage in the case of standard MOSFETs has been amended and a
close to linear proportionality has been achieved:
RDS ( on ) ⋅ A ∝ (VBr ) n
2,4...2,6 Standard MOS
n=
TM
Cool MOS
 1,3
It follows from this that the on-state losses Pstat present in the switch when transferring a particular power are:
2
2
Pstat ∝ I sw,eff ⋅ RDS ( on ) ∝ Pout ⋅ VBr
n −2
Therefore, whereas the losses increase with the operating voltage when using a standard MOSFET(proportional
to V 0,4…0,6 ), the losses are reduced using CoolMOS™ transistors proportionally to V -0,7.
CoolMOSTM 900V series has the world’s lowest area-specific RDS(on) for 900V MOSFETs as shown Figure 4,
which results in lowest RDS(on) per package type. 120mΩ in TO247 and 340mΩ in TO220 result in low
conduction losses and high current handling capability. Continuous drain currents up to 36A and pulse currents
up to 96A are possible (CoolMOS™ 900V 120mΩ). A comparison of available RDS(on)-values in DPak, TO220
and TO247 are given in Figure 4.
8
1.4
5
4
3
2
1.2
1
0.8
0.6
0.4
1
0.2
0
0
D-Pak
Figure 4
Other 900V MOSFET 1
Other 900V MOSFET 2
Other 900V MOSFET 3
CoolMOS™ 900V
1.6
RDSon [Ohm]
6
RDSon [Ohm]
1.8
Other 900V MOSFET 1
Other 900V MOSFET 2
Other 900V MOSFET 3
CoolMOS™ 900V
7
TO-220
TO-220
TO-247
TO-247
Comparison of RDS(on),max for best-in-class 900V devices (Right: Zoom-in TO220/TO247)
Application Note
8
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
The CoolMOS™ 900V cuts down the achievable RDS(on) in both packages by nearly a factor of four. By
introducing our new CoolMOS™ 900V technology we establish also a reduction of the total gate charge. The
new technology reduces the total gate charge Qg for similar RDS(on) types by 25% (Figure 5) and offers the lowest
FOM (RDS(on) x Qg) in this voltage class. The FOM on the one hand a measure of the conduction losses attributed
to the switch, on the other hand it correlates with the Qg a parameter being related to the energy the driver
circuit has to offer to turn the switch on and off. A very low FOM stands therefore for low conduction losses,
easy driving and low switching losses.
80
100
70
Other 900V MOSFET 1
Other 900V MOSFET 2
60
Other 900V MOSFET 3
Other 900V MOSFET 4
90
Qg*RDSon [Ohm*nC]
Qg [nC]
CoolMOS™ 900V
50
40
30
20
80
70
Other 900V MOSFET 1
Other 900V MOSFET 2
Other 900V MOSFET 3
Other 900V MOSFET 4
60
50
40
30
20
10
10
0
0
Figure 5
CoolMOS™ 900V
Gate Charge QG and Figute-of-merit (RDS(on) x QG) values for 900V devices with nearly
same RDS(on) of 1.3-1.4Ω
Not only has the new technology achieved breakthrough at reduced RDS(on) values, but new benchmarks have
also been set for the device capacitances. A second effect to be considered in the switching losses is the
energy being stored in the output capacitance. This energy Eoss (Figure 6) is transfered into heat during hard
switched turn-on. Due to the strongly nonlinear voltage dependence of the output capacitance the 900V
CoolMOS™ compensation devices offer here a very good performance if switched to more than 150V (marked
in Figure 6).
Eoss [µJ]
Energy stored in the output capacitance of the MOSFETs is reduced by a factor of two or more at working
voltage.
8
7
6
5
4
3
2
1
0
Other 900V MOSFET 1
Other 900V MOSFET 2
Other 900V MOSFET 3
Other 900V MOSFET 4
CoolMOS™ 900V
0
Figure 6
100
200
300
VDS [V]
400
500
Eoss values for different 900V MOSFETs
Application Note
9
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
Target applications CoolMOSTM 900V
3
The new CoolMOSTM 900V serie offers more design flexibility and pushes the existing limits towards higher
power without significant disadvantages. Designers of power units benefit from the high blocking voltage, low
RDS(on) and low Gate charge of the new CoolMOSTM 900V. Some examples are explained in the following
paragraphs.
3.1
Wide range designs (90…270Vac) with their typical 400Vdc bulk voltage
Designs for standard grid voltages can benefit from the higher blocking voltage. Depending on the application
the efficiency can be increased and/or design can be simplified without additional costs or other disadvantages.
Example 1: 500W Single Transistor Forward (STF) Converter used in ATX power supplies
Major benefits with CoolMOSTM 900V:
•
500W output power achievable with STF
•
higher efficiency (+0.7% with BiC TO220)
•
lower cost and part count
•
easier design (no high side control)
compared to TTF
The output power benchmark for STF converters can be increased by using CoolMOSTM 900V. Up to 500W is
achievable with a single MOSFET with increased performance and lower costs compared to standard TwoTransistor-Forward (TTF) with 200mΩ 500V/600V MOSFETs. Figure 7 shows the schematics of both
topologies. In the STF we have only one transistor compared to the two transistors and the pulse transformer in
a TTF.
TTF
Figure 7
STF
ATX power supplies (secondary side schematic being simplified).
Application Note
10
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
Changing the topology from TTF to STF not only simplifies the design and adds layout benefits without the
disadvantages (like the need of high-side-switching) of TTF.
Table 2 shows a comparison of the primary side losses of TTF and STF. Working frequency is 100kHz.
Table 2
Losses comparison Two-Transistor-Forward vs. Single-Transistor-Forward Converter
TTF with
200mΩ/600V
STF with
500mΩ/900V
STF with
340mΩ/900V
Conduction
6.5W
8.1W
5.5W
Output capacitance
2.8W
1.0W
2.1W
Switching
7.3W
4.7W
4.7W
---
0.5W
0.5W
16.6W
14.3W
12.8W
Losses
Demagnetizing winding
Total losses
Despite the higher RDS(on) of the CoolMOSTM 900V it is possible to design a STF with a higher efficiency than a
TTF with 200mΩ 600V MOSFETs. This is due to the higher dynamic losses in a TTF because in every cycle two
transistors have to be switched compared to only one transistor in a STF.
Indeed the transformer in a STF needs an additional demagnetizing winding which causes a small amount of
losses which do not exist in TTF topology. But with careful design (bifilar winding) these losses can be very low
and don´t influence the result significant.
Cost optimized designs use the 500mΩ CoolMOSTM 900V with slightly increased efficiency (compared to TTF
with 200mΩ MOSFETs) and reducing losses up to 0.7% is possible using the 340mΩ CoolMOSTM 900V.
Application Note
11
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
Example 2: 200W Quasiresonant Flyback converters for LCD-TV
Major benefits with CoolMOSTM 900V:
•
more than 200W of output power achievable with Quasi-Resonant Flyback
•
improved EMI behavior due to true zero-voltage switching
•
higher efficiency (+0.7% compared to 600V or 650V parts, 0.2% compared to 800V parts)
•
lower voltage stress on secondary diodes or synchronous rectifiers
Modern LCD-TV require output power up to 200W with high efficieny of the power supply together with low
costs. The best topology for these requirements is the Quasi-Resonant Flyback Converter (QR-FB) and its
disadvantages (like the high peak voltage on primary switch) are easy to handle with CoolMOSTM 900V.
Figure 8
Quasi-Resonant Flyback Converter for LCD-TV (schematic simplified on secondary)
MOSFETs with high blocking voltage allow optimized transformer design resulting in reduced semiconductor
losses and reduced voltage stress on secondary diode or synchronous rectifier.
Efficiency improvement of 0.2% compared to availabe 800V parts and even 0.7% compared to standard 650V
parts is possible using CoolMOSTM 900V.
Table 3 shows the results of a 200W / 24V Quasiresonant Flyback design realized with 650V, 800V and 900V
MOSFETs, respectively at a switching frequeny of 100kHz
Application Note
12
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
Table 3
200W / 24V Quasiresonant Flyback with different types of MOSFETs
Benefit by using CoolMOS™ 900V
650V
500mΩ
CoolMOS
800V
500mΩ
CoolMOS
900V
500mΩ
CoolMOS
Duty Cycle
at Vin,min and max load
18%
27%
32%
Longer DC tue to higher reflected
voltage
Peak current
4.8 A
3.1 A
2.7 A
Reduced peak current
Conduction losses
1.35 W
0.90W
0.76 W
Reduced conduction loss
Turn-on-losses
0.17 W
0.09 W
0
True zero-voltage switching! Æ
Improved EMI behaviour!
Turn-off-losses
1.4 W
0.9 W
0.8 W
Reduced turn-off loss due to lower peak
current
Voltage stress on
secondary side diode
91 V
57V
48V
Reduced voltage stress on sec. side
diode or sync.rec MOSFET
Total losses
6.6 W
5.6 W
5.2 W
Efficiency loss
3.31 %
2.80 %
2.61 %
Application Note
13
Significant loss reduction!
0.7% vs. 650V
0.2% vs. 800V
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
3.2
Replacement of IGBTs by CoolMOS™ 900V Series
Using a MOSFET with its Ohmic forward characteristic allow a significant reduction of conduction losses below
the power dissipation of IGBTs where conduction losses can not fall below the on-set voltage times load current.
PFC and PWM stages are possible to up to 750V bulk voltage using CoolMOSTM 900V without diminishing
safety margin.
Example 3: Renewable energy applications / solar converters
TM
Major benefits with CoolMOS
900V:
•
more panels in series possible→lower copper losses in wiring
•
higher overall efficiency
•
no Overvoltage Protection (OVP) necessary
•
smaller magnetic components due to higher switching frequency
Figure 9
Typical DC / AC Solar Converter (with Overvoltage Protection)
Renewable energy applications such as photovoltaic converters show very high efficiency requirements due to
system amortization via pay back of electricity fed back into the public network.
The use of MOSFETs instead of IGBTs enhances the efficiency especially in the mid range of output power - as
being characteristic especially for many days in central and Northern Europe – by avoiding the characteristic
onset voltage of the IGBT. The clear disadvantage of the MOSFET, its limited blocking voltage range and its
more than square-law between RDS(on) and BVDSS is amended by the new MOS generation CoolMOSTM 900 V.
This new product family allows to build converters with an enlarged input voltage range coming thus closer to
the upper limit of 1000 V as defined by the IEC 60364 for solar modules. Putting more panels in series instead
of paralleling reduces significantly cabling losses, efforts and costs. Alone the cabling losses can be cut by
factor of 2 when changing from 600 to 900 V voltage class.
Another factor in photovoltaic systems is size and cost of magnetic components. Offering a device with
improved RDS(on) x Qg and RDS(on) x Eoss performance allows an increase of switching frequency without suffering
from the penalty of increased losses. Therefore reduction of system size is possible without losing energy
efficiency.
Application Note
14
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
3.3
Lighting applications
Using SEPIC topology as PFC converter eliminates high inrush current and improve surge current capability.
With CoolMOSTM 900V the necessary higher blocking voltage compared to standard PFC boost topology can be
handled.
Figure 10
Lamp ballast with SEPIC preconverter
Additionally the 3-Phase-Supply of Lamp ballasts for street lighting and greenhouses requires a higher voltage
capability than is offered with 600V or 800V MOSFETs, and lower on-resistance than what is offered with
conventional 900V MOSFETs.
Ballasts for Flat Fluorescent Lamps require switches with a higher voltage capability due to the favored single
switch resonant topology.
3.4
Auxiliary power supplies in 3-phase systems
Using a 3-phase grid the blocking voltage of the MOSFETs in auxiliary power supplies needs to be higher than
800V. With CoolMOSTM 900V Flyback converters even for higher output power levels are easy to design thanks
to low conduction, switching and driving losses.
Figure 11
Flyback Converter for auxiliary power supplies
Application Note
15
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
4
Product Portfolio
CoolMOSTM 900V portfolio in Figure 12 will be filled up during 2008.
Figure 12
CoolMOSTM 900V Products.
Figure 13
Naming System for CoolMOSTM Products
Application Note
16
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
5
Circuit Design and Layout Recommendations
There are a number of recommendations to make with respect to circuit design and layout practices which will
assure a combination of high performance and reliability. They can be recommended as if “in order of
importance”, but realistically all are important, both in contribution toward circuit stability and reliability as well as
overall efficiency and performance. They are not that dissimilar to recommendations made for the introduction of
MOSFETs compared to bipolar transistors, or CoolMOSTM compared with standard MOSFETs; it is a matter of
the degree of care.
5.1
Control dv/dt and di/dt by Proper Selection of Gate Resistor
In order to exert full Rg control on the device maximum turn-off dv/dt we recommend the following procedure:
1) Check for highest peak current in the application
2) Choose Rg accordingly not to exceed 50 V/ns (maximum rating in datasheet)
3) At normal operation condition quasi ZVS condition can be expected, which gives best efficiency results
5.2
Minimize Parasitic Gate-Drain Board Capacitance
Particularly care must be spent on the coupling capacitances between gate and drain traces on the PCB. As
fast switching MOSFETs are capable to reach extremely high dv/dt values any coupling of the voltage rise at the
TM
drain into the gate circuit may disturb proper device control via the gate electrode. As the CoolMOS series
reaches extremely low values of the internal Cgd capacitance (Crss in datasheet), we recommend keeping layout
coupling capacitances below the internal capacitance of the device to exert full device control via the gate
circuit. Figure 14 shows a good example, where the gate and drain traces are either perpendicular to each other
or go into different directions with virtually no overlap or paralleling to each other. A “bad“ layout example is
shown as reference to the good layout in Figure 15.
If possible, use source foils or ground-plane to shield the gate from the drain connection.
Two independent
Totem Pol Drivers
as close as
possible to the
MOSFET!
View Top Layer
View Bottom Layer
Heatsink
Heatsink
Separate and short
source inductance to
reference point for gate
drive!
Figure 14
Minimized couple
capacitance
between gate and
drain pin!
Heatsink is connected to source (GND)!!
Good Layout Example Ensuring Clean Waveforms When Designing in CoolMOSTM
Application Note
17
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
Decoupling
capacitor far away
from gate pin of
the MOSFET & ONLY
One Driver Stage
for two MOSFET
High source inductance
-
GND connection of the
decoupling capacitor C2
far away from the driver
stage
Heatsink
High parasitic
capacitance between
gate and drain!
Figure 15
5.3
Bad Layout Example
Locate Gate Drivers and Gate Turn-Off Components as Close as Possible to
the Gate
Always locate the gate drive as close as possible to the driven MOSFET and the gate resistor in close proximity
of the gate pin. This prevents it acting as an antenna for capacitively coupled signals. The controller/IC driver
should be capable of providing a strong “low” level drive with voltage as near to ground as possible- MOS or
bipolar/MOS composite output stages work well in that regard, due to low output saturation voltages. While
some drivers may be deemed to have sufficient margin under static or “DC” conditions, with ground bounce,
source inductance drop, etc, the operating margin to assure “off” mode can quickly disappear.
5.4
Use Symmetrical Layout for Paralleling MOSFETs, and Good Isolation of
Gate Drive between FETs
We recommend the use of multi-channel gate drivers in order to have separate channels for each MOSFET.
Physical layout should be as symmetrical as possible, with the low impedance driver located as close as
possible to the MOSFETs and on a symmetric axis.
5.5
Summary
To summarize, below recommendations are important when designing in CoolMOSTM 900V to reach highest
efficiency with clean waveforms and low EMI stress.
✓
Control dv/dt and di/dt by proper selection of gate resistor
✓
Minimize parasitic gate-drain capacitance on board
✓
Locate gate drivers and gate turn-off components as close as possible to the gate
✓
Use symmetrical layout for paralleling
Application Note
18
V1.3, 2008-05
CoolMOS™ 900V
New 900V class for superjunction devices
A new horizon for SMPS and renewable energy applictions
References
[1]
T. Fujihira: “Theory of Semiconductor Superjunction Devices”, Jpn.J.Appl.Phys., Vol. 36, pp. 62546262, 1997.
[2]
A.W. Ludikhuize, “A review of the RESURF technology”, Proc. ISPSD 2000, pp. 11-18.
[3]
X. B. Chen and C. Hu, “Optimum doping profile of power MOSFET’s epitaxial Layer”, IEEE Trans.
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[4]
G. Deboy, M. März, J.-P. Stengl, H. Strack, J. Tihanyi, H. Weber, “A new generation of high voltage
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Application Note
19
V1.3, 2008-05
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