Introduction to our simulation models for IGBTs and ...

26
Application Note Please read the Important Notice and Warnings at the end of this document V 1.0 www.infineon.com page 1 of 26 2020-10-16 AN 2020-17 Introduction to Infineon’s simulation models for IGBTs and silicon diodes in discrete packages About this document Scope and purpose The document provides an introduction to and explanation of Infineon’s simulation models for discrete IGBTs and silicon diodes. Intended audience The document is intended for R&D staff and enigneers who want to perform a first evaluation of the Infineon discrete and IGBTs and silicon diodes by means of electrical and thermal simulations. Table of contents About this document ....................................................................................................................... 1 Table of contents ............................................................................................................................ 1 1 Introduction .......................................................................................................................... 3 2 Infineon SPICE models for IGBTs and power silicon diodes .......................................................... 4 2.1 Model library files .................................................................................................................................... 4 2.1.1 File types............................................................................................................................................. 4 2.1.2 Library implementation in SIMetrix................................................................................................... 5 2.1.2.1 Install the model ........................................................................................................................... 5 2.1.2.2 Associate model with symbol ....................................................................................................... 6 2.1.3 Library implementation in LTspice® .................................................................................................. 8 2.1.3.1 Install the model ........................................................................................................................... 8 2.1.3.2 Associate the model with symbol................................................................................................. 9 2.2 Modelling levels ..................................................................................................................................... 10 2.2.1 Level 1 (behavioral modelling approach) [2] .................................................................................. 11 2.2.2 Level 2 (physics-based modelling approach) [3],[4] ....................................................................... 12 2.2.3 Level 3 (coupled electro-thermal modelling) ................................................................................. 12 2.3 IGBT models for 4-pin devices .............................................................................................................. 14 2.4 Typical simulation parameters ............................................................................................................. 14 2.5 Transient simulation results ................................................................................................................. 16 2.5.1 Level 1 vs. Level 2 calibration .......................................................................................................... 16 2.5.2 Level 1 vs. Level 2 transient behavior .............................................................................................. 18 3 Conclusion ........................................................................................................................... 23 4 Contact address .................................................................................................................... 24 5 References ........................................................................................................................... 25 Revision history............................................................................................................................. 25

Transcript of Introduction to our simulation models for IGBTs and ...

Page 1: Introduction to our simulation models for IGBTs and ...

Application Note Please read the Important Notice and Warnings at the end of this document V 1.0

www.infineon.com page 1 of 26 2020-10-16

AN 2020-17

Introduction to Infineon’s simulation models

for IGBTs and silicon diodes in discrete

packages

About this document

Scope and purpose

The document provides an introduction to and explanation of Infineon’s simulation models for discrete IGBTs

and silicon diodes.

Intended audience

The document is intended for R&D staff and enigneers who want to perform a first evaluation of the Infineon discrete and IGBTs and silicon diodes by means of electrical and thermal simulations.

Table of contents

About this document ....................................................................................................................... 1

Table of contents ............................................................................................................................ 1

1 Introduction .......................................................................................................................... 3

2 Infineon SPICE models for IGBTs and power silicon diodes .......................................................... 4

2.1 Model library files .................................................................................................................................... 4 2.1.1 File types ............................................................................................................................................. 4

2.1.2 Library implementation in SIMetrix ................................................................................................... 5 2.1.2.1 Install the model ........................................................................................................................... 5 2.1.2.2 Associate model with symbol ....................................................................................................... 6

2.1.3 Library implementation in LTspice® .................................................................................................. 8 2.1.3.1 Install the model ........................................................................................................................... 8

2.1.3.2 Associate the model with symbol................................................................................................. 9 2.2 Modelling levels ..................................................................................................................................... 10

2.2.1 Level 1 (behavioral modelling approach) [2] .................................................................................. 11

2.2.2 Level 2 (physics-based modelling approach) [3],[4] ....................................................................... 12 2.2.3 Level 3 (coupled electro-thermal modelling) ................................................................................. 12

2.3 IGBT models for 4-pin devices .............................................................................................................. 14 2.4 Typical simulation parameters ............................................................................................................. 14

2.5 Transient simulation results ................................................................................................................. 16 2.5.1 Level 1 vs. Level 2 calibration .......................................................................................................... 16 2.5.2 Level 1 vs. Level 2 transient behavior .............................................................................................. 18

3 Conclusion ........................................................................................................................... 23

4 Contact address .................................................................................................................... 24

5 References ........................................................................................................................... 25

Revision history............................................................................................................................. 25

Page 2: Introduction to our simulation models for IGBTs and ...

Application Note 2 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Introduction

Page 3: Introduction to our simulation models for IGBTs and ...

Application Note 3 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

1 Introduction

Models provided by Infineon are not warranted as fully representing all the specifications and operating

characteristics of the semiconductor products to which the model relates. The models describe the characteristics of typical devices. In all cases, the current datasheet information for a given device provides the

only guaranteed performance specifications that can be used as a design guideline. Although models can be a useful tool in evaluating device performance, they cannot model exact device behavior and characteristics under all conditions, nor are they intended to replace experimental tests for the final verification of the

application system. Infineon therefore does not assume any liability arising from the improper use of these

models. Infineon reserves the right to modify models without prior notice.

Page 4: Introduction to our simulation models for IGBTs and ...

Application Note 4 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

2 Infineon SPICE1 models for IGBTs and power silicon diodes

2.1 Model library files

The models for Infineon IGBTs and power silicon diodes are evaluated with the SIMetrix circuit simulator. The models are tested, verified and provided in PSpice® simulation code. All power device models are grouped in dedicated library files, according to their voltage class and product technology.

2.1.1 File types

The available model files consist of the file types given inTable 1.

Table 1

File type Simulator Description Support

.lib SIMetrix,

LTspice®,

OrCAD® PSpice®

Files comprising the PSpice®-

compatible model code

All Infineon IGBT and power silicon diode

products

.sxslb SIMetrix

Files comprising model symbols required by the SIMetrix graphic

user interface

See Section 0

.asy

LTspice® Files comprising model symbols required by the LTspice® graphic

user interface

Add directory where .asy files are stored in the control panel in the “Sym. & Lib. Search

Path”

.slb OrCAD® Files comprising model symbols required by the graphic user

interface ‘Schematics.’

In order to be usable in evaluation versions of PSpice®

system, each symbol library

does not contain more than

twenty symbols.

Needs to be installed via the menu ‘Options

→ Editor Configuration → Library Settings’.

Can be imported to OrCAD® and converted

to .olb files.

1 Simulation program with integrated circuit emphasis.

Page 5: Introduction to our simulation models for IGBTs and ...

Application Note 5 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

File type Simulator Description Support

.olb OrCAD®

Capture

Files comprising model symbols required by the graphic user

interface ‘Capture’

If ‘Schematics’ is used, the .lib files must be installed via the ‘Analysis → Library and

Include Files’ menu. Permanent installation

by ‘Add Library’ is recommended

The .lib files are available on the Infineon website [1] and on each specific product page.

2.1.2 Library implementation in SIMetrix

Before setting up a simulation, a model must be integrated in the simulator tool. This section gives an

introduction about the installation of the simulation model files in SIMetrix. All simulation models are installed using a two-step procedure:

Install the model

Associate the model with a symbol

2.1.2.1 Install the model

SIMetrix presents two ways of model installation: “drag and drop method” and “local installation method.”

To install a model with a drag-and-drop method, follow the steps below (the steps are also summarized in Figure 1):

− Open Windows Explorer and locate the device models

− Select items to be installed (the files with extensions .lib and .sxslb)

− Make sure that the SIMetrix command shell is in focus. If not, select a schematic or graph and press the

spacebar

− Select the files in Windows Explorer, then drag and drop them into the command shell

− For files that are processed individually, a message box will pop up. Once confirmed, the simulation model will be installed

Page 6: Introduction to our simulation models for IGBTs and ...

Application Note 6 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

Figure 1 Install a model in SIMetrix with the drag-and-drop method

A model can also be enabled for a certain schematic simply by including a reference in the Command Window (local installation method). The following steps can be used to include the model in the schematic (as also

shown in Figure 2):

− Open the schematic sheet, press F11 on keyboard to toggle Command Window

− Use either .include, .inc, .library or .lib commands followed by the library name. In case the model library

file (.lib) is not placed in the same folder of the schematic, the full path to the file must be used

Figure 2 Install a model in SIMetrix with the local installation method

2.1.2.2 Associate model with symbol

Once the simulation model is installed, the proper part can be placed on the schematic. If the model has been installed with the “drag-and-drop method,” the procedure is the following:

− To associate a symbol to a newly installed library, go to Place → From Model Library (Figure 3a)

− The newly installed part can be found in the “Recently Added Models” section. Once the partis selected,

and if the related symbol has been installed, a preview of the symbol is shown in the preview windows, as depicted in Figure 3b

− In case the symbol has not been installed, the simulator displays a warning that a symbol cannot be found. In this case, to generate a standard symbol for the model, it is sufficient to press “Place” and then

“Auto Create Symbol”, as shown in Figure 3c and Figure 3d

− If the part will be placed in the “Unassigned” category, press OK (Figure 3e) and select Yes; leave at “Unassigned” (Figure 3f), otherwise select a proper category or create a new one

− The symbol is now ready to be placed in the schematic

a) b)

Page 7: Introduction to our simulation models for IGBTs and ...

Application Note 7 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

c) d)

e) f)

Figure 3 Associate installed models with symbols in SIMetrix

To associate the symbol with a model that has been just included in the simulation (local installation method),

the following steps must be followed (Figure 4):

− Select “Place” and press “From Symbol Library…”

− Select an appropriate symbol (e.g. “Semiconductors,” “IGBT”). Please note that the number of pins of the

symbol must be the same as indicated in the model file .lib file

− Place the symbol within your user-defined schematic

− Combine the locally installed library with the placed symbol:

− Define “MODEL” as X in order to make use of an arbitrary sub-circuit

− Define “VALUE” as the model name you want to use. The model names can be retrieved from the library

file (e.g., IKW50N65H5_L1)

Page 8: Introduction to our simulation models for IGBTs and ...

Application Note 8 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

Figure 4 Associate locally installed model with a symbol

2.1.3 Library implementation in LTspice®

This section gives an introduction about the installation of the simulation model files in LTspice®. All simulation models are installed using a two-step procedure:

Install the model

Associate the model with a symbol

2.1.3.1 Install the model

In LTspice®, an external model can be easily enabled in the specific schematic. The latter can be done by using

one of the inclusion SPICE commands: “.include”, “.inc”, “.library” or “.lib”, followed by the library name, as shown in Figure 5. In case the model library file (.lib) is not placed in the same folder of the schematic, the full path to the file must be used.

In addition, the path to the model file can be permanently added to the simulator default searching paths. This can be done in the Control Panel of the software, by adding the path in the “Sym. & Lib. Search Path” section (“Library Search Path” area).

Page 9: Introduction to our simulation models for IGBTs and ...

Application Note 9 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

Figure 5 Include a model library in LTspice® schematic

2.1.3.2 Associate the model with symbol

A symbol file for LTspice® has the extension “.asy”. The symbol can be used in the software only if it is in the included search paths of the software, by adding it in the “Sym. & Lib. Search Path” section (“Symbol Search

Path” area).

Alternatively, the software can create automatically a symbol for the specific model. To do so, these are the

steps to follow:

− Open the library file with LTspice®

− Right click on the model name

− In the drop-down menu, select “Create Symbol,” then press “Yes” in the window that appears

− A general, editable symbol is then generated, with the same number of pins and pin names of the source

model. Also, any parameter that may be needed by the model is also visible (e.g parameter TJ in )

− The generated symbols can be found in the “AutoGenerated” folder1.

The entire procedure is show in Figure 6.

a) b)

1 The “AutoGenerated” models can be accessed directly by the software clicking on “Edit” menu and then “Component”.

Page 10: Introduction to our simulation models for IGBTs and ...

Application Note 10 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

c) d)

Figure 6 Create a generic symbol for a model in LTspice®

2.2 Modelling levels

Infineon provides up to three different types of models for IGBTs and power silicon diode devices. The differences among the models are related to the implementation of the electrical characteristics of the device

as well as to the implementation of dynamic temperature-dependent simulations. The nomenclature of the models is the device name followed by a suffix identifying the level:

Table 2 Modelling level nomenclature

Suffix Model Level

_L1 1

_L2 2

_L3 3

For example, the Level 1 model of the IKW50N65F5 has the model name IKW50N65F5_L1.

The pin naming is defined as follows:

* PINS:

* ---------------------------------------------------------------------------

* | PIN | DESCRIPTION

* ---------------------------------------------------------------------------

* | C | IGBT collector for single devices and DuoPacks

* ---------------------------------------------------------------------------

* | G | IGBT gate for single devices and DuoPacks

* ---------------------------------------------------------------------------

* | E | IGBT emitter for single devices and DuoPacks

* ---------------------------------------------------------------------------

* | K | IGBT Kelvin emitter sense for single devices and DuoPacks

* ---------------------------------------------------------------------------

* | A | diode anode for single devices

Page 11: Introduction to our simulation models for IGBTs and ...

Application Note 11 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

* ---------------------------------------------------------------------------

* | C | diode cathode for single devices

* ---------------------------------------------------------------------------

* | tc | case temperature

* ---------------------------------------------------------------------------

* | tj | junction temperature for IGBTs or single diodes

* ---------------------------------------------------------------------------

* | tjd | junction temperature for diodes within a DuoPack

The table below offers a condensed overview of the different levels and their preferred usage.

Table 3 Usage of model levels

Level Terminals Use-case suggestion

L1 For IGBTs: C, G, E (K)

For diodes: A, C

The Level 1 model is based on a behavioral description of the electrical characteristics of the device [1]. The calibration is done with

respect to the latest datasheet content. The transient calibration procedure is based on the ”Dynamic test circuit”, which is stated in

the latest datasheet using the information of parasitic elements and

nominal conditions given in the table ”Switching Characteristic,

Inductive Load.”

L2 The parameters of Level 2 compact models are based on technological data and device physics. The model is calibrated by

means of dedicated measurements (output, transfer and gate-charge

curves).

L31 For IGBTs: C, G, E (K),

tc, tj, (tjd)

For diodes: A, C, tc, tj

Level 3 models have three additional pins: tc, tj and tjd. The voltage

level of pins tc, tj and tjd indicates the case temperature, the IGBT junction temperature and the diode junction temperature,

respectively, at any time in degrees Celsius (see Section 3.3).

Level 3 models must be used only for transient analysis, except short circuit. In order to calculate the transient device’s junction

temperature, a model of the thermal path from case to ambient is

required, which has to be included by the user as a suitable

dimensioned Cauer RC network connected at one side to the pin tc and at the other side to a node that is set to the desired ambient

temperature with a voltage source referenced to thermal ground.

Alternatively, the pin tc can be connected to a fixed voltage source to

perform isothermal simuations.

2.2.1 Level 1 (behavioral modelling approach) [2]

The diode as well as the IGBT model consist of two interdependent subcircuits: the main circuit, which de-scribes the outer electrical characteristics of the device, and an auxiliary circuit used to calculate the amount of stored charge as the result of a bipolar effect. The usage of the compact models is restricted to a temperature range between 25°C and the maximum allowed junction temperature, which is stated in the corresponding

1 Due to the high modelling effort, level 3 models of IGBTs and diodes are provided only upon request.

Page 12: Introduction to our simulation models for IGBTs and ...

Application Note 12 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

datasheet. The static temperature of the model can be set by using the SPICE command “.TEMP” in the simulator interface.

2.2.2 Level 2 (physics-based modelling approach) [3],[4]

Level 2 compact models are based on the discretization of device-physic equations to one dimension current flow (as shown in Figure 7). The simplification is done in order to achieve acceptable runtimes and model

development cycles. Level 2 compact models can also model second-order effects of the devices (e.g. sharp tail current cut-off, diode reverse recovery snap-off, etc.) even though to a limited extent.

Figure 7 Vertical doping profile of a typical pin diode along with the basic nodes used to describe the

diode behavior

2.2.3 Level 3 (coupled electro-thermal modelling)

In order to be able to compute the self-heating dynamically, the electrical model (Level 1 or Level 2) is coupled with a thermal model of the mounted device, including the package, in a so-called Level 3 model. Therefore

Level 3 compact models include a suitable dimensioned Cauer RC network describing the thermal path from the IGBT/diode junction (located inside the chips) to the back side of the lead frame (corresponding to the case). To achieve the self-heating, the instantaneous power dissipation in the transistor/diode is continuously

calculated and a current proportional to this power is fed into the equivalent thermal network. The voltage at the nodes tj and tjd contain the information about the time-dependent junction temperature of the IGBT and the diode, respectively, which in turn is fed back directly to the corresponding temperature-dependent electrical model. The Level 3 model symbol is extended by thermal nodes with the junction temperatures and the case temperature, and has 5 pins in the case of a single-packed IGBT, and 6 pins in the case of a duo-packed

IGBT, as depicted in Fig. 3.7.

Page 13: Introduction to our simulation models for IGBTs and ...

Application Note 13 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

Single-packed IGBT with thermal

nodes

Co-packed IGBT and diode with

thermal nodes

3D geometry of a co-packed IGBT and diode: leadframe is in grey and

chip is in green

Figure 8 Schematic symbols of Level 3 IGBT models for electro-thermal calculation

The temperature connections are working as voltage nodes and are electrically separated from the electrical device model. Therefore, a potential difference of 1 V refers to a temperature difference of 1°C. The additional thermal nodes tj and tjd enable the user to easily monitor the simulated junction temperature of the IGBT and the diode, respectively. Usually, these nodes should not be connected. However, in case the initial temperature

of the device has to be different than the thermal equilibrium, a small capacitor (typically 1 pF) can be

connected between these nodes and the thermal ground. The initial temperature can then be set on the capacitor by means of the .IC SPICE instruction. The small capacitor does not alter the thermal network, and is only used to force the initial temperature. The thermal node tc contains the information about the case

temperature, which is the temperature on the back side of the lead frame. In the model it can be constant or

time dependent. This node has always to be connected to a reference voltage/temperature, either directly (to

simulate a constant case temperature) or by means of an external thermal RC network (e.g. when the case is connected to a thermal pad and to a heat sink). The reference temperature can also be time dependent, in

case, for example, it represents the temperature of a heat sink.

a) b)

Figure 9 Connecting external thermal networks to devices modelled with Level 3 approach: a)

connection by means of additional thermal network; b) connection to a fixed reference

temperature

Figure 9 depicts an example of a simulation with external heat sink. In the left picture, R1 can refer, as an example, to the thermal resistance of the interface between the case of the device and heat sink (e.g. a thermal

pad). In this case, C1 and R2 model the transient thermal behavior of the heat sink, representing its thermal

capacitance and thermal resistance to the environment, respectively. The voltage source connected to R2 describes the time-dependent ambient temperature behavior for the simulation. An alternative connection

Page 14: Introduction to our simulation models for IGBTs and ...

Application Note 14 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

method is shown in Figure 9b, where the case of the package is fixed to 25°C. With such a connection, and by

changing the value of the source, it is possible to exploit the variations of the device parameters (e.g. VCEsat, VF,

etc.) with the temperature, to replicate the information shown in the datasheet graphs (this possibility is also offered by the Level 1 and Level 2 models, by means of the parameter “TEMP”).

2.3 IGBT models for 4-pin devices

Some Infineon IGBT portfolios also include products with separate emitter connections for fast and efficient switching behavior of the IGBT. These products feature an additional connection for the gate-driving return

path, called the Kelvin emitter (K)1. The 4-pin models have four terminals and require a dedicated symbol with an additional pin, compared to the standard 3-pin symbol of an IGBT. The models include the internal parasitic emitter inductance of the bond wires and the emitter pin of the package until the ideal solder point, defined to

be 4.5 mm from the mold of the package, as given in the 3-pin configuration according to the datasheet

specification. In the 4-pin model a separate, internal parasitic inductance is included corresponding to the contribution of the Kelvin emitter bond wire and pin.

Figure 10 Simulation circuit for 4-in IGBT devices

In addition to the parasitic inductance of the package, the PCB layout contributes to increasing the overall parasitic inductance of the gate loop. Thus, the simulation schematic should consider this addional

contribution, by including an external parasitic inductance as shown in Figure 10. As a first order of approximation for the stray inductance, a value of 1nH per mm of trace length can be used. Alternatively, a

more precise value of stray inductance can be determined by performing a 3D simulation of the PCB geometry.

2.4 Typical simulation parameters

The following setting has been found to be helpful for simulation with the indicated circuit simulator tools.

Table 4 Simulator settings for SIMetrix, OrCAD® PSpice®, LTspice®

OPTION Level 1 Level 2

Method Gear Gear

1 For further information, the users can refer to the dedicated application note: “TRENCHSTOP™ 5 IGBT in a Kevin Emitter

Configuration”.

Page 15: Introduction to our simulation models for IGBTs and ...

Application Note 15 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

OPTION Level 1 Level 2

AbsTol 1e-9 1e-9

VnTol 1e-6 1e-6

RelTol 1e-3 1e-3

ITL1 200 200

ITL2 200 200

ITL4 25 50

POINTTOL (only Simetrix) - 1

CONV (only Simetrix)1 - >1

In OrCAD® PSpice®, it is also recommended to enable the Advanced Convergence Algorithms (as shown in

Figure 11).

Figure 11 OrCAD® PSpice® runtime settings

In many cases, it is necessary to limit the step size for transient analyses. As a typical power electronic circuit contains elements with different time scales, the automatic step control of the simulators can sometimes disregard essential fast time-scale information, which eventually leads to convergence problems. In the latter

case, limiting the maximum stepsize to a value of 1 ns can help to solve the issues.

In cases where the time to be simulated (TSTOP) is relatively large (typically if thermal phenomena are of main

interest) and sharp gradients occur (e.g. in the startup phase of the system), the required simulation time might be too long. In those cases, it is helpful to start a first simulation with a shorter simulation time, and save the simulation status. Then a second simulation can be started from the saved state, with a relaxed timestep.

1 Only if convergence fails.

Page 16: Introduction to our simulation models for IGBTs and ...

Application Note 16 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

2.5 Transient simulation results

This section is aimed to show the differences between Level 1 and Level 2 models with respect to the transient turn-on and turn-off curves in a standard double-pulse test circuit, taking as an example the model of the

IKW25N120H3 IGBT.

2.5.1 Level 1 vs. Level 2 calibration

The following are used for the calibration of a Level 1 IGBT model:

the transfer curves at 25°C and Tjmax

the output curves for different VGE values at 25°C and Tjmax

the gate-charge curves at 20% and 80% VCE

the capacitance as a function of VCE

the switching energies and switching times at 25°C and Tjmax, both at nominal gate resistance, load current

and DC-link voltage

The following are used for the calibration of the Level 1 diode model:

the VF curves at 25°C and Tjmax

the Qrr and Irr values at 25°C and Tjmax

In contrast, the calibration of Level 2 models is performed only with the gate-charge curve and static curves

with the output characteristic at VGE=15 V.

Figure 12 to Figure 16 show that the calibrated static and gate-charge curves are very similar for both model

levels.

a) b)

Figure 12 Output characteristics @ Tj = 25°C of the KW25N120H3: a) datasheet, b) simulation

Page 17: Introduction to our simulation models for IGBTs and ...

Application Note 17 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

a) b)

Figure 13 Output characteristics @ Tj = 175°C of the KW25N120H3: a) datasheet, b) simulation

a) b)

Figure 14 Transfer characteristics @VCE = 20 Vof the KW25N120H3: a) datasheet, b) simulation

Page 18: Introduction to our simulation models for IGBTs and ...

Application Note 18 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

a) b)

Figure 15 Gate-charge characteristics @IC = 25 A of the KW25N120H3: a) datasheet, b) simulation

a) b)

Figure 16 Diode output characteristics of the KW25N120H3: a) datasheet, b) simulation

2.5.2 Level 1 vs. Level 2 transient behavior

This section is aimed to show the precision of the compact models with regard to the switching characteristics of the IGBT and the power diode, and to depict the differences between very closely calibrated behavioral

(Level 1) and physics-based (Level 2) models in representing the behavior of the device.

Page 19: Introduction to our simulation models for IGBTs and ...

Application Note 19 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

a) b)

Figure 17 Turn-on transient curves of the IKW25N120H3 for nominal switching conditions (Tj=25°C,

VCC=600 V, IC=25 A, RG=20 Ω): a) measurements, b) simulation

a) b)

Figure 18 Turn-off transient curves of the IKW25N120H3 for nominal switching conditions (Tj=25°C,

VCC=600 V, IC=25 A, RG=20 Ω): a) measurements, b) simulation

Page 20: Introduction to our simulation models for IGBTs and ...

Application Note 20 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

Figure 17 and Figure 18 depict the waveforms during the turn-on and turn-off switching events at nominal operating conditions as obtained by measurement and simulation, respectively. From the comparison it can be concluded that both Level 1 and Level 2 models represent the transient behavior of the IGBT with good accuracy. The most pronounced difference from the experimental results is the shape of the collector current at

turn-off. The differences between Level 1 and Level 2 are mainly visible in the reverse-recovery current at turn-on and the overvoltage peak at turn-off. The Level 2 modelling approach gives the closest results with respect to the experimental waevforms, as it considers 1D physical effects and the real vertical design of the power diode. In contrast, the Level 1 behavioral model represents the reverse-recovery current by an exponential

decay function, which is not always accurate. In addition, Level 1 does not model at all the forward-recovery

effect of the diode, which is partially responsible for the overvoltage peak at turn-off.

Figure 19 and Figure 20 show the simulated curves with the variation of the gate resistance and the load

current, respectively. The differences between Level 1 and Level 2 models are the same as for nominal operating conditions, with the exception of the 50 A load current (twice nominal current), where the deviations become more significant, affecting the accuracy of the turn-on energy losses. This is pointed out in Figure 21,

which depicts the overlay of the load current dependency of the switching energy losses, as given in the datasheet, with the values extracted from the simulated transient curves. Since the behavioral Level 1 model is calibrated on the switching energies for nominal conditions, Eon and Eoff match quite well to the data-sheet values at 25 A, whereas for the Level 2 model, the deviation is less than 30%. The Level 2 model, which is

calibrated only on static characteristics and the gate-charge curves, predicts reasonably the transient behavior

of the device, as it is based on semiconductor physics. Its benefit becomes clear when the load current is 50 A:

since the Level 1 model is not calibrated for that operation, the error is higher than 30% whilst the error of the Level 2 model is lower than 10%.

a) b)

Figure 19 Simulated transient curves of the IKW25N120H3 for nominal switching conditions (Tj=25°C,

VCC=600 V, IC=25 A) with gate resistance variation: a) turn-on, b) turn-off

Page 21: Introduction to our simulation models for IGBTs and ...

Application Note 21 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

a) b)

Figure 20 Simulated transient curves of the IKW25N120H3 for nominal switching conditions (Tj=25°C,

VCC=600 V, RG=20 Ω) with load current variation: a) turn-on, b) turn-off

Page 22: Introduction to our simulation models for IGBTs and ...

Application Note 22 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

Figure 21 Comparison of datasheet and simulation current dependency of switching energy losses for

the IKW25N120H3 (Tj=25°C, VCC=600 V, RG=23 Ω, VGE=15/0 V)

In conclusion, Level 1 and Level 2 compact models for the IGBT are useful simulation tools aimed to perform

electrical simulations where the electrical behavior of the device is represented with a decent accuracy. When

the priority is the simulation speed, Level 1 models should be preferred. In case a more precise representation of the switching transients is needed, beyond the nominal operating point, it is recommended to simulate with the physics-based Level 2 models.

Page 23: Introduction to our simulation models for IGBTs and ...

Application Note 23 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

3 Conclusion

Infineon Technologies AG provides several simulation models for the silicon IGBTs and power diodes:

Level 1 models offer fast computational times and good accuracy within the calibrated conditions. It is the best choice whenever SPICE simulations are run according to the datasheet test conditions. Longer simulation runs (10 seconds or more) can be performed with acceptable computational times.

Level 2 models offer slower computation times but give more accurate results over a wider range of conditions. These models should be used if simulations have to be performed with test conditions that are not covered by the datasheet (e.g. different Rgs, different stray inductances, different supply voltages, etc.). With Level 2 models, short simulations (up to 10 seconds) are preferable due to longer computational efforts.

Page 24: Introduction to our simulation models for IGBTs and ...

Application Note 24 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Table of contents

4 Contact address

In case of further questions related to simulation models, the user can contact infineon local sales offices or by

sending an email to this address: [email protected].

Page 25: Introduction to our simulation models for IGBTs and ...

Application Note 25 of 26 V 1.0

2020-10-16

Introduction to Infineon’s simulation models for IGBTs and silicon

diodes in discrete packages Revision history

5 References

[1] https://www.infineon.com/cms/en/product/power/igbt/?redirId=54367#!simulation

[2] D. Ludwig, G. Alia, A. Biswas, M. Cotorogea, Behavioral compact models of IGBTs and Si-diodes for data sheet simulations using a machine learning based calibration strategy, PCIM Europe digital days 2020, 7 – 8 July 2020, pp. 494-501

[3] R. Kraus, K. Hoffmann, An Analytical Model of IGBTs with Low Emitter Efficiency, IEEE 1993.

[4] R. Kraus, P. Tuerkes, J. Sigg, Physics-based Models of power semiconductor devices for the circuit

simulator PSPICE, IEEE 1998.

[5] https://www.plexim.com/sites/default/files/plecsmanual.pdf

Revision history

Document

version

Date of release Description of changes

1.0 12-10-2020 First version

Page 26: Introduction to our simulation models for IGBTs and ...

Trademarks All referenced product or service names and trademarks are the property of their respective owners.

Edition 2020-10-16

AN 2020-17

Published by

Infineon Technologies AG

81726 Munich, Germany

© 2020 Infineon Technologies AG.

All Rights Reserved.

Do you have a question about this

document?

Email: [email protected]

Document reference

IMPORTANT NOTICE The information contained in this application note is given as a hint for the implementation of the product only and shall in no event be regarded as a description or warranty of a certain functionality, condition or quality of the product. Before implementation of the product, the recipient of this application note must verify any function and other technical information given herein in the real application. Infineon Technologies hereby disclaims any and all warranties and liabilities of any kind (including without limitation warranties of non-infringement of intellectual property rights of any third party) with respect to any and all information given in this application note. The data contained in this document is exclusively intended for technically trained staff. It is the responsibility of customer’s technical departments to evaluate the suitability of the product for the intended application and the completeness of the product information given in this document with respect to such application.

For further information on the product, technology, delivery terms and conditions and prices please contact your nearest Infineon Technologies office (www.infineon.com). Please note that this product is not qualified according to the AEC Q100 or AEC Q101 documents of the Automotive Electronics Council.

WARNINGS Due to technical requirements products may contain dangerous substances. For information on the types in question please contact your nearest Infineon Technologies office. Except as otherwise explicitly approved by Infineon Technologies in a written document signed by authorized representatives of Infineon Technologies, Infineon Technologies’ products may not be used in any applications where a failure of the product or any consequences of the use thereof can reasonably be expected to result in personal injury.