This document summarizes the modeling parameters and simulation results for a power MOSFET model. It includes: 1) The component modeled is a 2SK4078 power MOSFET from NEC with a standard diode model. Modeling parameters like threshold voltage, transconductance, resistances, and capacitances are provided. 2) Simulation results graph the transconductance, Vgs-Id, Rds(on), gate charge, capacitance, switching time, forward/reverse characteristics and compare to measurement data. Errors are less than 5% for most characteristics. 3) The reverse recovery characteristic of the body diode is also modeled and compared to measurement, with less than 1% error

1. Device Modeling Report
COMPONENTS: Power MOSFET (Model Parameters)
PART NUMBER: 2SK4078
MANUFACTURER: NEC
Body Diode : (Standard Model )
Bee Technologies Inc.
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

2. MOSFET MODEL
PSpice model
Model description
parameter
LEVEL
L Channel Length
W Channel Width
KP Transconductance
RS Source Ohmic Resistance
RD Ohmic Drain Resistance
VTO Zero-bias Threshold Voltage
RDS Drain-Source Shunt Resistance
TOX Gate Oxide Thickness
CGSO Zero-bias Gate-Source Capacitance
CGDO Zero-bias Gate-Drain Capacitance
CBD Zero-bias Bulk-Drain Junction Capacitance
MJ Bulk Junction Grading Coefficient
PB Bulk Junction Potential
FC Bulk Junction Forward-bias Capacitance Coefficient
RG Gate Ohmic Resistance
IS Bulk Junction Saturation Current
N Bulk Junction Emission Coefficient
RB Bulk Series Resistance
PHI Surface Inversion Potential
GAMMA Body-effect Parameter
DELTA Width effect on Threshold Voltage
ETA Static Feedback on Threshold Voltage
THETA Mobility Modulation
KAPPA Saturation Field Factor
VMAX Maximum Drift Velocity of Carriers
XJ Metallurgical Junction Depth
UO Surface Mobility
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3. Transconductance Characteristic
Circuit Simulation Result
Comparison table
gfs
Id(A) Error(%)
Measurement Simulation
1.00 2.900 2.961 2.09
2.00 2.950 3.009 1.99
5.00 3.080 3.105 0.82
10.00 3.215 3.217 0.05
20.00 3.380 3.378 -0.05
50.00 3.740 3.713 -0.71
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

4. Vgs-Id Characteristic
Circuit Simulation result
100A
10A
1.0A
0V 1.0V 2.0V 3.0V 4.0V 5.0V
I(Vsense)
V_VGS
Evaluation circuit
Vsense
U2
2SK4078
VDS
10Vdc
VGS
0
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

5. Comparison Graph
Circuit Simulation Result
Simulation Result
VGS(V)
ID(A) Measurement Simulation Error (%)
1.00 2.825 2.955 4.61
2.00 2.930 3.000 2.39
5.00 3.080 3.090 0.32
10.00 3.190 3.200 0.31
20.00 3.348 3.350 0.06
50.00 3.615 3.660 1.24
100.00 3.950 4.040 2.28
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

6. Rds(on) Characteristic
Circuit Simulation result
25A
20A
15A
10A
5A
0A
0V 40.0mV 80.0mV 120.0mV 157.5mV
I(Vsense)
V_VDS
Evaluation circuit
Vsense
U1
2SK4078 VDS
10Vdc
VGS
10Vdc
0
Simulation Result
ID = 25A, VGS = 10V Measurement Simulation Error (%)
R DS (on) m 6.3 6.3 0.00
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

7. Gate Charge Characteristic
Circuit Simulation result
12V
10V
8V
6V
4V
2V
0V
0 10n 20n 30n 40n 50n
V(W1:2)
Time*1mA
Evaluation circuit
Vsense
I1
U1 D1 50Adc
2SK4078 Dbreak
W1
+
I2
-
W VD
TD = 0 ION = 0A 32Vdc
1m IOFF = 1mA
I1 = 0
0
Simulation Result
VDD=32V, ID=50A,
Measurement Simulation Error (%)
VGS=10V
Qgs nC 7.00 6.96 -0.57
Qgd nC 13.00 12.96 -0.31
Qg nC 45.00 28.34 -37.02
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

8. Capacitance Characteristic
Measurement
Simulation
Simulation Result
Cbd (pF)
VDS (V) Error(%)
Measurement Simulation
0.10 500.00 510.00 -1.96
0.20 470.00 475.00 -1.05
0.50 400.00 403.00 -0.74
1.00 340.00 342.00 -0.58
2.00 270.00 271.00 -0.37
5.00 190.00 192.00 -1.04
10.00 145.00 147.00 -1.36
20.00 110.00 113.00 -2.65
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

9. Switching Time Characteristic
Circuit Simulation result
12V
10V
8V
6V
4V
2V
0V
-2V
4.94us 4.96us 4.98us 5.00us 5.02us 5.04us 5.06us 5.08us
V(2) V(3)/2
Time
Evaluation circuit
Vsense L2
3
50nH
R1
L3 RL
2 U2 0.8
2SK4078
10 30nH
V1 = 0
V2 = 20 V1 R2
TD = 5u 10 VDD
TR = 10n 20Vdc
TF = 10n
PW = 10u
PER = 10m
0 0 0 0
Simulation Result
ID=25A, VDD=20V
Measurement Simulation Error(%)
VGS=0/10V
td(on) ns 12.00 11.93 -0.58
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

10. Output Characteristic
Circuit Simulation result
150A
125A
VGS=10V
100A
4.5V
75A
50A
25A
0A
0V 0.5V 1.0V 1.5V 2.0V
I(Vsense)
V_VDS
Evaluation circuit
Vsense
U1
2SK4078
VDS
10Vdc
VGS
0
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

11. Forward Current Characteristic
Circuit Simulation Result
100A
10A
1.0A
100mA
10mA
0V 0.5V 1.0V 1.5V
I(R1)
V_V1
Evaluation Circuit
R1
0.01m
V1 U1
0Vdc 2SK4078
0
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

12. Comparison Graph
Circuit Simulation Result
Simulation Result
VSD(V)
IDR(A) %Error
Measurement Simulation
0.01 0.570 0.569 -0.18
0.10 0.630 0.632 0.32
0.20 0.650 0.651 0.15
0.50 0.680 0.676 -0.59
1.00 0.700 0.696 -0.57
2.00 0.718 0.717 -0.14
5.00 0.750 0.750 0.00
10.00 0.780 0.780 0.00
20.00 0.820 0.823 0.37
50.00 0.920 0.918 -0.17
100.00 1.050 1.051 0.12
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008

13. Reverse Recovery Characteristics (Body Diode)
Circuit Simulation Result
400mA
300mA
200mA
100mA
-0mA
-100mA
-200mA
-300mA
-400mA
9.92us 10.00us 10.08us 10.16us 10.24us
I(R1)
Time
Evaluation Circuit
R1
50
V1 = -9.4V V1
V2 = 10.6V U1
TD = 50n 2SK4078
TR = 10ns
TF = 10ns
PW = 10us
PER = 100us
0
Compare Measurement vs. Simulation
Measurement Simulation Error (%)
trj ns 19.20 19.02 -0.94
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14. Reverse Recovery Characteristic Reference
Measurement
Trj=19.2(ns)
Trb=44.8(ns)
Conditions:Ifwd=lrev=0.2(A),Rl=50
Example
Relation between trj and trb
All Rights Reserved Copyright (c) Bee Technologies Inc. 2008