Understanding Littelfuse Ignition IGBTs Datasheets/media/electronics/application_notes/... · Ignition IGBTs Datasheets 2019 Littelfuse Littelfuse.com The Challenge During the design

1

Application Note

Understanding Littelfuse Ignition IGBTs Datasheets

Littelfuse.com© 2019 Littelfuse

The Challenge During the design and development process of ignition platforms, system designers must consider several different constraints, parameters and working conditions specific to the final application of the system at hand. To take full advantage of the characteristics of the selected devices and ensure proper performance over a wide operating range, engineers must analyze each of the components’ specific characteristics and ensure the selected devices can provide safe operation under normal and worst-case scenarios during the lifetime of the ignition system. Understanding all the parameters contained in the semiconductor device’s datasheet is a demanding task, but it is one of an electronics design engineer’s most important skills.

The Solution This application note provides an overview of all the parameters contained in a datasheet of Littelfuse Ignition Insulated Gate Bipolar Transistors (ignition IGBTs); studying it will help designers to interpret and use the information provided to develop robust and reliable ignition systems.

Importance of Littelfuse Datasheets Littelfuse ignition IGBTs datasheets provide ignition system designers with all the information and electrical characteristics required to select the appropriate semiconductor device for each ignition platform. Static and dynamic characteristics are presented under different working conditions, providing a wide overview on the behavior of the device.

Introduction Littelfuse ignition IGBTs are based on a planar structure that makes them capable of withstanding high transient energy and voltage spikes while providing low power dissipation during conduction, making them ideal for ignition system applications. Figure 1 illustrates the electrical scheme of Littelfuse ignition IGBTs.

Figure 1. Ignition IGBT scheme. LGDxxxx/NGDxxxx and LGBxxxx/NGBxxxx are available with and without series gate resistance (RG).

E

C

RG

RGE

G

C

E

G

R GE

https://www.littelfuse.com/

2

Application Note

© 2019 Littelfuse Littelfuse.com

Ignition IGBTs are provided in DPAK (LGDxxxx/NGDxxxx) and D2PAK (LGBxxxx/NGBxxxx) packages, providing ignition systems designers the flexibility to meet demanding size constraints. Littelfuse ignition IGBT devices are available with (Figure 1, left) and without (Figure 1, right) series gate resistance (RG). Review the datasheet of each device for specific product details.

For the purpose of this application note, the NGD8201AN Series Ignition IGBT datasheet will be used as an example.

Mechanical Characteristics

Package Outline and Package Dimensions General information related to the packages available for each part number is provided on the first page of the datasheet. The specific information on dimensions and recommended PCB footprint are provided at the end (Figure 2).

Figure 2. Package outline and package dimensions information.

Notes: 1. Dimensioning and tolerances per ASMEY14.5M, 1994. 2. Controlling dimension: inch. 3. Thermal pad contour optional within dimensions b3, L3 and Z. 4. Dimensions D and E do not include mold flash, protrusions, or burrs. Mold flash, protrusions, or gate burrs shall not exceed 0.006 inches per side. 5. Dimensions D and E are determined at the outermost extremes of the plastic body. 6. Datums A and B are determined at datum plane H.

b

D

E

b3

L3

L4b2

M0.005 (0).13 C

c2A

c

C

Z

12 3

4

A1

H

A

B

C

L1L

H

L2 GAUGEPLANE

e

Z

NOTE 7Bottom View Bottom View

AlternateConstruction

SeatingPlane

Side View

Top View

Detail ARotated 90°C W

Detail A

DimInches Millimeters

Min Max Min Max

A 0.086 0.094 2.18 2.38

A1 0.000 0.005 0.00 0.13

b 0.025 0.035 0.63 0.89

b2 0.028 0.045 0.72 1.14

b3 0.180 0.215 4.57 5.46

c 0.018 0.024 0.46 0.61

c2 0.018 0.024 0.46 0.61

D 0.235 0.245 5.97 6.22

E 0.250 0.265 6.35 6.73

e 0.090 BSC 2.29 BSC

H 0.370 0.410 9.40 10.41

L 0.055 0.070 1.40 1.78

L1 0.114 REF 2.90 REF

L2 0.020 BSC 0.51 BSC

L3 0.035 0.050 0.89 1.27

L4 −−− 0.040 −−− 1.01

Z 0.155 −−− 3.93 −−−


3

Application Note


Device Number, Marking Diagram and Ordering Information The device number (Figure 3) summarizes the key characteristics of the device. The product class, technology, family, package, polarity, device ratings, performance attributes and shipping format are contained within this code. Littelfuse uses three types of numbering, for indicating devices related to the Motorola legacy series (Figure 3a), the reduced VCE(on) series (Figure 3b), or new product developments (Figure 3c).

Product Class L: Std Part X: Proprietary

Technology G: IGBT

Package D: DPAK/TO252 B : D2PAK/TO263 S: D2PAK/Straight Lead

Current Rating 15: 15A

Channel N: N Channel P : P Channel

Voltage Rating 41: 41*10 in Volts

Version A: Version A B: Version B : Skip if No Revision

Packing T : Tape & Reel U: Tube R: Reverse Taping Pack

Internal Emitter Ballast H : Ballast Structure Design I: No Ballast Structure Design

a.

Reduced Vceon Version 82 : Two Digits

Sequential Identifier 01: Two Digits

Product ClassL: Std Part X: Proprietary

Package D: DPAK/TO252 B : D2PAK/TO263 S: D2PAK/Straight Lead TechnologyG: IGBT

Version A: Version A B: Version B : Skip if No Revision


Internal Emitter BallastH : Ballast Structure DesignI: No Ballast Structure Design

b.

Product ClassL: Std Part X: Proprietary

Technology

G: IGBT

Voltage Rating45: 45*10 in Volts

Energy Rating30: 30*10 in mJ

Package D: DPAK/TO252 B : D2PAK/TO263 S: D2PAK/Straight Lead

Version A: Version A

Generation5: Gen 54: Gen 4

Qualification LevelA: Automotive Qualified

B: Version B : Skip if No Revision


Figure 3. Device number. Motorola legacy series (a), reduced VCE(ON) series (b), and new product developments (c).

c.


4

Application Note


Figure 4a

The device marking diagram (Figure 4a) contains the basic information regarding the pin numbering/identification and the device code. This section also includes an explanation of the manufacturing information contained within the device code.

The ordering information (i.e., device ordering number, semiconductor package type, shipping package and quantity) is summarized in a table for easy referral (Figure 4b), in the last page of the datasheet.

Figure 4. Marking diagram (a) and ordering information (b).

Footprint and Soldering The mechanical dimensions and recommended footprint of the device are provided at the end of the datasheet, as shown in Figure 5. The power dissipation capability of the device in a DPAK or D2PAK package is highly dependent on the collector pad size. As a general rule, the collector pad footprint for a DPAK should be twice as large as that used in a D2PAK for the same amount of power dissipation capability.

Figure 5. Recommended soldering footprint.

Maximum Temperature for Soldering Purposes The maximum allowable lead temperature during soldering. To avoid device failure due to excessive heating, it is necessary to follow the recommended soldering temperature and soldering time guidelines. Please refer to the standard J-STD-020D for the recommended soldering profile.

Device Package Shipping†

NGD8201ANT4GDPAK

(Pb−Free)2,500 /

Tape & Reel

NGD8201Ax = Device CodeY = Year

M = MonthA = Assembly Site

XX = Lot Serial Code

5.800.228

2.580.102

1.600.063

6.200.244

3.000.118

6.170.243

mminchesSCALE 3:1

LF8201AG

4 Collector

2 Collector

1Gate

3Emitter

YMAXX

NGD

a.

b.


5

Application Note


Electrical Characteristics

This section summarizes the electrical characteristics of the ignition IGBT under different operating points. Each parameter is accompanied by an explanation of the conditions used during the test.

Maximum Ratings The maximum ratings at which the selected ignition IGBT can be operated are listed on the first page of the semiconductor’s datasheet in a table that summarizes the electrical and thermal limits of the device. The semiconductor should never be operated at ratings higher than those indicated in this table. Failure to do so may result in abnormal behavior and/or physical damage. Table 1 lists the maximum ratings for the NGD8201AN.

Notice that operation within the maximum ratings does not guarantee that the device will meet the datasheet specifications if the application conditions are different from those specified in the datasheet (i.e. operating points, ambient temperature).

Collector to Emitter Voltage VCES Maximum voltage that the ignition IGBT can withstand between collector and emitter without being damaged. This parameter is measured with gate and emitter biased to 0V or to a negative voltage not higher than the maximum (VGE) specified in the datasheet.

Collector to Gate Voltage VCER Maximum voltage that the ignition IGBT can withstand between collector and gate without being damaged.

Gate to Emitter Voltage VGE Maximum allowable voltage between the gate and the emitter of the IGBT.

Collector Current IC Maximum allowable current through the collector at a given case temperature (TC). This value is established by determining the continuous and pulsed collector current that is required to reach the maximum junction temperature (TJ =150°C or TJ =175°C) at a specific case temperature.

The maximum collector current under specific operating conditions can be estimated based on the thermal-junction- to-case resistance (Rth(J-C) ), the collector-to-emitter ON state voltage (VCE(on) ) of the device and the case and junction temperatures.

Rating Symbol Value Unit

Collector−Emitter Voltage VCES 440 V

Gate−Gate Voltage VCES 440 V

Gate−Emitter Voltage VGE ± 15 V

Collector Current−Continuous@ TC = 25°C − Pulsed IC

2050

ADC AAC

Continous Gate Current IG 1.0 mA

Transient Gate Current (t ≤ 2 ms, f ≤ 100 Hz) IG 20 mA

ESD (Charged–Device Model) ESD 2.0 kV

ESD (Human Body Model) R = 1500 Ω, C = 100 pF ESD 2.0 kV

ESD (Machine Model) R = 0 Ω, C = 200 pF ESD 500 V

Total Power Dissipation @ TC = 25°C Derate above 25°C PD

1250.83

WW/°C

Operating and Storage Temperature Range TJ, Tstg

−55 to +175 °C

Table 1. NGD8201AN Ignition IGBT maximum ratings. Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability.

IC =TJ—TC

Rth(J-C) * VCE(on)


6

Application Note


Figures 4 to 6 in the datasheet provide the collector current at a given junction temperature, gate to emitter voltage and collector to emitter voltage (Figure 6).

Figure 6. Collector current vs. collector-emitter voltage at different junction temperature and gate-to-emitter voltage values.

4.5V

4V

3.5V

3V

2.5V

VGE=10V

5V

TJ=175ºC

VCE, Collector to Emitter Voltage (V)

I C, Col

lect

or C

urre

nt (A

)

0 654321 7 80

60

50

40

30

20

10


0 654321 7 8

I C, Col

lect

or C

urre

nt (A

)

0

60

50

40

30

20

10

3.5V

3V

2.5V

4V4.5VVGE = 10V

5V

TJ= 25ºC

3.5V

3V

2.5V


0 654321 7 8

I C, Col

lect

or C

urre

nt (A

)

0

60

50

40

30

20

10

4V4.5VVGE = 10V

TJ=–40ºC

5V


7

Application Note


Continuous Gate Current IG Maximum allowable continuous current through the gate. This current is directly related to the internal series gate resistance (RG) and the gate to emitter resistance (RGE).

Transient Gate Current IG Maximum allowable transient current through the gate. This current is specified at a maximum frequency and time of duration.

ESD Electrostatic Discharge (ESD) can be defined as the sudden flow of energy between two electrically charged elements due to either direct contact or dielectric breakdown. Semiconductors are tested, for qualification, under three different models, namely the Charged Device Model (CDM), the Human Body Model (HBM) and the Machine Model (MM).

Total Power Dissipation PD Maximum power that the device is capable of dissipating during operation. This value is estimated considering a case temperature of 25°C and a maximum junction temperature of 150°C or 175°C (depending on the specific device).

The power dissipation capability will be reduced for case temperatures above 25°C. In the particular case of the NGD8201A, the derating will be of 0.83 W⁄ °C. The power dissipation capability at a specific operating point can be estimated based on the case and junction temperature and the device junction-to-case resistance.

Operating and Storage Temperature The operating temperature indicates the recommended junction temperature (TJ ) range at which the device can function reliably without physical or electrical damage or a reduction in its life expectancy.

The storage temperature (Tstg) indicates the recommended temperature range at which the device should be stored, without the need of an electrical bias, in order to not affect its life expectancy.

PD =TJ—TC

Rth(J-C)

CDM (Charged Device Model) HBM (Human Body Model) MM (Machine Model)

The Charged Device Model (CDM) considers the discharge event on a semiconductor due to contact with a conductive material.

The Human Body Model (HBM) considers the discharge event on a semiconductor due to contact with a charged human being.

The Machine Model (MM) considers the discharge event on a semiconductor due to contact with a charged object (e.g., production equipment).


8

Application Note


Avalanche Characteristics

The avalanche characteristics of the ignition IGBTs are determined using the setup shown in Figure 7, where the collector of the device under test (the ignition IGBT) is connected to a load inductance whose value emulates the ignition coil inductance, and a DC power supply. The gate pulsed signal is emulated by means of a signal generator connected to the gate through a driver stage and a series gate resistance.

Figure 7. Test circuit used to determine the ignition IGBT's avalanche characteristics.

Collector to Emitter Avalanche Energy EAS Under normal operation of the ignition system, when the gate voltage (VGE) changes from ON to OFF state (discharging cycle), the energy stored in the leakage inductance (LS) of the ignition coil is dissipated on the ignition IGBT, while the energy stored in the magnetizing inductance (Lm) is used in the combustion process in the ignition chamber. However, when an open collector fault occurs due to a defective spark plug or a loose connection in the secondary of the ignition coil, all the energy stored in the ignition coil (that is, the energy stored in both the leakage and the magnetizing inductance) will be dissipated through the ignition IGBT. As a result, it is recommended that the selected ignition IGBT can withstand all the energy stored in the ignition coil. This energy can be estimated based on the values of the leakage and magnetizing inductances, and the current, as follows:

Notice that the energy provided by the battery is not considered in this estimation. This is mostly because its value is negligible when compared to the energy stored in the ignition coil, and that part of it will be dissipated in the parasitic resistance of the ignition coil.

Table 2. Avalanche characteristics.

EAS = 1/2 * (Ls+Lm) * I 2

L

Function Generator

VCC

R E

RGext

DUTT1T2

VGE

T 1T 2

V GE

R GE

R G

Driver

V GE


Single Pulse Collector−to−Emitter Avalanche Energy

VCC = 50 V, VGE = 5.0 V, Pk IL = 16.7 A, RG = 1000 Ω , L = 1.8 mH, Starting TJ = 25°C

EAS

250

mJVCC = 50 V, VGE = 5.0 V, Pk IL = 14.9 A, RG = 1000 Ω , L = 3.0 mH, Starting TJ = 150°C 200

VCC = 50 V, VGE = 5.0 V, Pk IL = 14.1 A, RG = 1000 Ω , L = 1.8 mH, Starting TJ = 175°C 180

Reverse Avalanche Energy

VCC = 100 V, VGE = 20 V, Pk IL = 25.8 A, L = 6.0 mH, Starting TJ = 25°C EAS (R) 2000 mJ


9

Application Note


Littelfuse datasheets provide the maximum avalanche energy that the ignition IGBT can withstand during normal operation as well as the maximum avalanche current under an open secondary condition. Table 2 summarizes the achievable avalanche energy considering different junction temperatures at specific working conditions, under normal operation. Notice that as the junction temperature increases, the avalanche energy capability of the device decreases. For more information on the energy capability of the device under different load inductance values and junction temperatures, please refer to Figure 1 in the NGD8201AN datasheet (Figure 8).

Figure 8. Avalanche energy vs. inductive load value at different junction temperatures.

Additionally, the maximum sustainable current under an open secondary, is shown in Figure 9 (Figure 2 in the datasheet), where the device performance is evaluated considering different junction temperatures and load inductance values. Notice that the avalanche current capability of the device decreases with the increase in the junction temperature or the load inductance value.

Figure 9. Collector to emitter avalanche energy vs. inductive load value.

Reverse Avalanche Energy EAS(R) The reverse avalanche energy indicates the maximum energy capability of the ignition IGBT in reverse polarity. As in the collector-to-emitter avalanche parameter, this value is determined by testing the device response under a single pulse.

Inductor (mH)

SCIS

Ene

rgy

(mJ)

0 642 8 100

300

350

400

250

200

150

100

50

TJ=25ºC

TJ=175ºC

VCC=14VVGE=5.0VRG=1000Ω

TJ, Junction Temperature (˚C)

-50 12510075500 25-25 150 175

I A, A

vala

nche

Cur

rent

(A)

0

30

25

20

15

10

5

L = 1.8 mH

L = 3.0 mH

L = 10 mH

VCC=14VVGE=5.0VRG=1000Ω


10

Application Note


Thermal Characteristics

Table 3 summarizes the thermal characteristics of the ignition IGBT.

Table 3. Thermal Characteristics 1. When surface mounted to an FR4 board using the minimum recommended pad size.

The semiconductor’s thermal behavior depends on the properties of the different layers within the device, starting from the silicon junction up to ambient (Figure 10a). In this path, each stage has a specific thermal impedance (Figure 10b), which will ultimately dictate the thermal performance of the device under steady state or transient operating conditions.

a. b.

Figure 10. Ignition IGBT layers (a) and equivalent thermal circuit under transient state (b).

Analyzing Figure 10, it is possible to see that the dissipated power (PD(t)) flowing through the semiconductor will result in a junction temperature (TJ ), given in terms of the specific resistance (Rθ) and capacitance (Cs ) of each layer and the ambient temperature (Ta ).

Thermal Resistance, Junction to Case RθJC This indicates the steady-state junction-to-case thermal resistance under continuous operation. This value is affected by the operating conditions. RθJC can be estimated based on the junction and case temperature (TC=25°C) at a certain dissipated power, as follows:

Under transient or pulsed operation, the transient thermal resistance (RθJC(t)) must be considered. As reproduced in Figure 11, Figure 14 from the NGD8201AN datasheet allows estimating the value of this resistance under different pulsed operating conditions, considering diverse duty cycles and pulse widths. Notice that with the increment of the duty cycle (longer pulse width), the transient thermal impedance approaches its steady-state value.

Silicon

Leadframe

PCB

T J

T S

T C

PD(t)

Solder

Mold Compound

T a

RΘ(Si)

PD(t)

RΘ(C) RΘ(PCB)T J T C T S

C S (Si) C S (C) C S (PCB)

T a

Thermal GND

RθJC =TJ—TC

PD


Thermal Resistance, Junction−to−Case RƟJC 1.3°C/W

Thermal Resistance, Junction to Ambient DPAK (Note 1) RƟJA 95

Maximum Lead Temperature for Soldering Purposes, 1/8” from case for 5 seconds TL 275 °C


11

Application Note


Figure 11. Ignition IGBT transient junction-to-case thermal resistance.

Thermal Resistance, Junction to Ambient RθJA Indicates the steady-state junction-to-ambient thermal resistance under continuous operation. This value is determined under specific operating conditions as indicated in the datasheet. During transient or pulsed operating conditions, the transient junction-to-ambient resistance (R(t)), shown in Figure 13 in the NGD8201AN datasheet must be used (Figure 12).

Figure 12. Ignition IGBT transient junction-to-ambient thermal resistance.

t, Time (S)

R θJC

(t), T

rans

ient

The

rmal

Res

ista

nce

(˚C/W

att)

10.10.010.01

0.1

10

1

0.0010.00010.000010.000001 10

0.01 Single PulseDuty Cycle, D=t1/t2

D Curves Apply for PowerPulse Train ShownRead Time at t1

TJ(pk) – TA= P(pk) RθJC(t)

P(pk)

t2

t1

Duty Cycle = 0.5

0.02

0.05

0.1

0.2

t, Time (S)

R(t),

Tra

nsie

nt T

herm

al R

esis

tanc

e (˚C

/Wat

t)

0.1

0.01

1

100

10

10.10.010.0010.00010.000010.000001 10 100 1000

Duty Cycle = 0.5

0.01

0.02

0.050.1

0.2

Single Pulse

D Curves Apply for PowerPulse Train ShownRead Time at t1

TJ(pk) – TA= P(pk) RθJA(t)

For D=1: RθJC ~ R(t) for t ≤ 0.1 sDuty Cycle, D=t1/t2

P(pk)

t2

t1


12

Application Note


OFF Characteristics

Table 4 summarizes the electric values of the ignition IGBT when in the OFF state.

Table 4. Ignition IGBT electrical characteristics in OFF state. Product parametric performance is indicated in the Electrical Characteristics for the listed test conditions, unless otherwise noted. Product performance may not be indicated by the Electrical Characteristics if operated under different conditions. *Maximum Value of Characteristic across Temperature Range.

Collector-Emitter Clamp Voltage (BVCES) Clamped voltage of the ignition IGBTs between collector and emitter during the ignition coil discharging cycle. Ignition IGBTs have a set of poly diodes in back-to-back configuration that ensure that this voltage value is not surpassed, actively clamping the collector to emitter voltage.

Zero Gate Voltage Collector Current ICES Leakage current flowing from the collector to the emitter when the ignition IGBT is in the OFF state (VG=0). Figure 8 in the datasheet (Figure 13), contains the leakage current considering the device operation under different collector-emitter voltage and junction temperatures.

Characteristic Symbol Test Conditions Temperature Min Typ Max Unit

Collector−Emitter Clamp Voltage BVCES

IC = 2.0 mA TJ = −40°C to 175°C 370 395 420V

IC = 10 mA TJ = −40°C to 175°C 390 415 440

Zero Gate Voltage Collector Current ICES

VCE = 15 VVGE = 0 V TJ = 25°C − 0.1 1.0

µAVCE = 200 V

VGE = 0 V

TJ = 25°C 0.5 1.5 10

TJ = 175°C 1.0 25 100*

TJ = −40°C 0.4 0.8 5.0

Reverse Collector−Emitter Clamp Voltage BVCES(R) IC = -75 mA

TJ = 25°C 30 35 39

VTJ = 175°C 35 39 45*

TJ = −40°C 30 33 37

Reverse Collector−Emitter Leakage Current ICES(R) VCE = −24 V

TJ = 25°C 0.05 0.2 1.0

mATJ = 175°C 1.0 8.5 25

TJ = −40°C 0.005 0.025 0.2

Gate−Emitter Clamp Voltage BVGES IG = ± 5.0 mA TJ = −40°C to 175°C 12 12.5 14 V

Gate−Emitter Leakage Current IGES VGE = ± 5.0 V TJ = −40°C to 175°C 200 300 350* µA

Gate Resistor RG _ TJ = −40°C to 175°C – 70 – Ω

Gate−Emitter Resistor RGE − TJ = −40°C to 175°C 14.25 16 25 kΩ


13

Application Note


Figure 13. Collector to emitter leakage current (ICES) vs. junction temperature and reverse collector-emitter leakage current (ICES(R)) vs. junction temperature.

Reverse Collector-Emitter Clamp Voltage BVCES(R) Maximum voltage that the device can withstand with inverse polarity (emitter to collector), also known as reverse battery condition.

Reverse Collector-Emitter Leakage Current ICES(R) Maximum emitter-to-collector leakage current. This current is determined at the rated emitter to collector voltage.

Gate-Emitter Clamp Voltage BVGES Clamping voltage of the ignition IGBT between gate and emitter. Ignition IGBTs have a set of Zener diodes between gate and emitter that protect the device during the discharging cycle of the ignition coil.

Gate-Emitter Leakage Current IGES Current flowing through the gate, with collector and emitter shorted at a given gate voltage.

Gate Resistor RG The gate series resistance, together with the external gate driver resistor, determines the switching behavior of the ignition IGBT. Furthermore, during the clamping period of operation of the ignition IGBT, the current that flows through the collector to gate clamping diodes creates a voltage across the series gate and the gate-emitter resistances, polarizing the ignition IGBT in the linear mode.

Gate-Emitter Resistor RGE The gate emitter resistance is used to polarize the ignition IGBT during the discharging cycle (clamping period) into the linear mode. Its value is several times larger than the gate resistance.


Colle

ctor

-to-

Emitt

er L

eaka

ge

Curr

ent (

μA)

–50 1007550250–25 125 150 1750.1

10000

1000

100

10

1.0

VCE = 200 V

VCE = –24 V


14

Application Note


ON Characteristics

Table 5 summarizes the electric values of the ignition IGBT when in the ON state (Note 3).

Table 5. Ignition IGBT electrical Characteristics in ON state. *Maximum Value of Characteristic across Temperature Range. 3. Pulse Test: Pulse Width ≤ 300 µS, Duty Cycle ≤ 2%.

Gate Threshold Voltage VGE(th) Minimum gate-to-emitter voltage at which a given collector-to-emitter current begins to flow. This value is specified at different junction temperatures, as shown in Figure 9 in the datasheet (Figure 14).


Gate Threshold Voltage VGE (th)

IC = 1.0 mA, VGE = VCE

TJ = 25°C 1.5 1.8 2.1

VTJ = 175°C 0.7 1.0 1.3

TJ = −40°C 1.7 2.0 2.3*

Threshold Temperature Coefficient (Negative) − − − 4.0 4.6 5.2 mV/°C

Collector−to−Emitter On−Voltage VCE (on)

IC = 6.5 A, VGE = 3.7 V

TJ = 25°C 0.85 1.03 1.35

V

TJ = 175°C 0.7 0.9 1.15

TJ = −40°C 0.09 1.11 1.4

IC =9.0 A, VGE = 3.9 V

TJ = 25°C 0.9 1.11 1.45

TJ = 175°C 0.8 1.01 1.25

TJ = −40°C 1.0 1.18 1.5

IC = 7.5 A, VGE = 4.5 V

TJ = 25°C 0.85 1.15 1.4

TJ = 175°C 0.7 0.95 1.2

TJ = −40°C 1.0 1.3 1.6*

IC = 10 A, VGE = 4.5 V

TJ = 25°C 1.0 1.3 1.6

TJ = 175°C 0.8 1.05 1.4

TJ = −40°C 1.1 1.4 1.7*

IC = 15 A, VGE = 4.5 V

TJ = 25°C 1.15 1.45 1.7

TJ = 175°C 1.0 1.3 1.55

TJ = −40°C 1.25 1.55 1.8*

IC = 20 A, VGE = 4.5 V

TJ = 25°C 1.1 1.4 1.9

TJ = 175°C 1.2 1.5 1.8

TJ = −40°C 1.3 1.42 2.0

Forward Transconductance gfs IC = 6.0 A,VCE = 5.0 V TJ = 25°C 10 18 25 Mhos


15

Application Note


Figure 14. Gate threshold voltage vs. junction temperature.

Threshold Temperature Coefficient (Negative) Rate at which an increase in the temperature of the device results in a decrease in the threshold voltage value.

Collector to Emitter ON State Voltage VCE(on) Voltage drop between collector and emitter during ON state. This voltage depends on the operating point of the ignition IGBT, varying depending on the gate to emitter voltage, collector current and the junction temperature. The value of the collector-to-emitter ON state voltage affects the ignition IGBT conduction losses.

In the datasheet, Figure 3 (reproduced here as Figure 15) indicates the behavior of the collector to emitter ON state voltage against the junction temperature (TJ), considering different collector currents (Ic) at a given gate emitter voltage (VGE).

Figure 15. Collector-to-emitter voltage vs. junction temperature under a given gate-to-emitter voltage and different collector currents.

Forward Transconductance gfs The transconductance, given in Siemens or Mhos, is defined as the ratio between the change in the collector current over the change in the gate to emitter voltage.

1.00

0.75

0.50

0.25

0

2.50

2.25

2.00

1.75

1.50

1.25

Mean


Gat

e Th

resh

old

Volta

ge (V

)

Mean + 4 σ

Mean – 4 σ

–50 1007550250–25 125 150 175

IC = 25 A

IC = 20 A


VGE = 4.5 V

V CE, C

olle

ctor

to E

mitt

er V

olta

ge (V

)

IC = 15 A

IC = 10 A

IC = 7.5 A

–50 1007550250–25 125 150 175

1.0

0.75

0.50

0.25

0.0

2.0

1.75

1.5

1.25

gfs =∆IC

∆VGE


16

Application Note


Dynamic Characteristics

Table 6 summarizes the values of ignition IGBTs parasitic capacitances during the transient state between ON-OFF and OFF-ON states. These values are not constant and are dependent on the applied collector-to-emitter voltage. The transient response of the ignition IGBT is heavily influenced by the parasitic capacitances.

Table 6. Ignition IGBT dynamic state characteristics.

Notice that the capacitances defined in Table 6 as the input (CISS), output (COSS) and the transfer (CRSS) capacitances correspond to the measurable capacitances in the component. These, in turn, depend on the different parasitic capacitances between the terminals of an ignition IGBT as shown in Figure 16, where the gate-to-collector (CGC), gate-to-emitter (CGE) and collector-to-emitter (CCE) capacitances are shown.

Figure 16. Parasitic capacitances of an ignition IGBT.

Input Capacitance CISS The input capacitance is formed by the parallel connection of the gate-to-collector and gate-to-emitter capacitances when the collector to emitter is shorted. The gate to emitter is considered as constant while the gate to collector capacitance is voltage dependent. The input capacitance is given by the following expression:

The input and transfer capacitances are of special interest for the proper design of the ignition IGBT gate drive.


Input Capacitance CISS

f = 10 kHzVCC = 25 V

TJ = -40ºC to

175°C

1100 1300 1500

pFOutput Capacitance COSS70 80 90

Transfer Capacitance CRSS 18 20 22

R GE

R GC CE

C GE

Gate

Collector

Emitter

C GC

CISS = CGE+CGC


17

Application Note


Output Capacitance COSS The output capacitance is formed by the parallel connection of the gate-to-collector and collector-to-emitter capacitances. Both gate-to-collector and collector-to-emitter capacitances are voltage dependent. The output capacitance is given by the following expression:

The rate of change of the collector-emitter voltage during the switching transition is dependent on the output capacitance value.

Transfer Capacitance CRSS The transfer (or Miller) capacitance is given in terms of the gate-to-collector parasitic capacitance. The value of this capacitance affects the Miller plateau observed on the gate voltage curve during the transient state.

The values of the input, output and transfer capacitances under different collector-emitter voltages can be found in Figure 10 in the datasheet (Figure 17).

Figure 17. Capacitance vs. collector-emitter voltage.


C, C

apac

itanc

e (p

F)

0 2520151050.1

10000

1000

100

10

1.0

CISS

COSS

CRSS

COSS = CGC+CCE

CRSS = CGC


18

Application Note


Switching Characteristics

The switching characteristics shown in Table 7 specify the transient response times of the ignition IGBT under different operating conditions. This information will help the designer ensure the device switching time is suitable for the intended application and for determining the switching energy losses.

Table 7. Ignition IGBT switching state characteristics.

Littelfuse datasheets contain the switching characteristics of the ignition IGBT at specific testing conditions considering resistive and inductive loads under different junction temperature values.

Turn-OFF Delay Time td(off) The turn-off delay is the elapsed time between the turn-off signal coming from the gate drive and the decrease in the collector current. This time is measured between the instant at which the gate voltage is at 90% of its ON-state value and the instant at which the collector to emitter current reaches 10% of its value. The values specified in the datasheet consider either a resistive or an inductive load.

Fall Time tf Time required for the collector current to decrease from 90% to 10% of its initial value. The values specified in the datasheet consider either a resistive or an inductive load.

The fall time and turn-OFF delay time of the device under different junction temperatures are given in the datasheet considering a resistive (Figure 11) and inductive (Figure 12) load as is depicted in Figure 18. The specific test conditions are also indicated in the figures.


Turn−Off Delay Time (Resistive) td (off)

VCC = 300 V IC = 9.0 A

RG = 1.0 kΩRL = 33 ΩVGE = 5.0 V

TJ = 25°C 6.0 8.0 10

µSec

TJ = 175°C 6.0 8.0 10

Fall Time (Resistive) tf

TJ = 25°C 4.0 6.0 8.0

TJ = 175°C 8.0 10.5 14

Turn−Off Delay Time (Inductive) td (off)

VCC = 300 V IC = 9.0 A

RG = 1.0 kΩL = 300 µHVGE = 5.0 V

TJ = 25°C 3.0 5.0 7.0

TJ = 175°C 5.0 7.0 9.0

Fall Time (Inductive) tf

TJ = 25°C 1.5 3.0 4.5

TJ = 175°C 5.0 7.0 10

Turn−On Delay Time td (on)VCC = 14 V IC = 9.0 A

RG = 1.0 kΩRL = 1.5 ΩVGE = 5.0 V

TJ = 25°C 1.0 1.5 2.0

TJ = 175°C 1.0 1.5 2.0

Rise Time tr

TJ = 25°C 4.0 6.0 8.0

TJ = 175°C 3.0 5.0 7.0


19

Application Note


Figure 18. Resistive- and inductive-switching fall time vs. temperature.

Turn-ON Delay Time td(on) The turn-on delay is the elapsed time between the turn-on signal coming from the gate drive and the increase in the collector current. This time is measured between the instant at which the gate voltage and the collector current reach 10% of their ON-state value.

Rise Time tr The time required for the collector current to increase from 10% to 90% of its final value.


Switc

hing

Tim

e (µ

s)

25 17515012510075500

12

10

08

06

04

02

VCC = 300 VVGE = 5.0 VRG = 1000 ΩIC = 9.0 ARL = 33 Ω

tfall

tdelay


Switc

hing

Tim

e (µ

s)

25 17515012510075500

12

10

08

06

04

02

VCC = 300 VVGE = 5.0 VRG = 1000 ΩIC = 9.0 AL = 300 μH

tfall

tdelay


20

Application Note


About the Authors

Dr. Hugo Guzman Application Engineer, Power Semiconductors Dr. Hugo Guzmán joined Littelfuse as an Application Engineer for Power Semiconductors in June 2017. He received the Ph.D. degree in mechatronic engineering from the University of Málaga in 2015, and is specialized in power electronics and control. Hugo has worked in automotive, industrial and renewable energy applications in a range of research, consultancy and industry positions since 2007. He is based in Lampertheim, Germany and can be reached at [email protected].

Changchao Ju Sr. Product Engineer Changchao Ju joined Littelfuse in October 2016 as Senior Product Engineer for Ignition Devices, Before joining Littelfuse he worked in the Automotive Business Unit as Product Engineer of discrete IGBTs and smart power module products at Fairchild From 2006 to 2016. He graduated from the University of Huai’an in Electronic Engineering in 2005. He is based in Wuxi, China and can be reached at [email protected].

Jose Padilla Global Product Marketing Manager, Discrete IGBTs and Ignition IGBTs

Jose Padilla joined Littelfuse in October 2016 as Global Product Marketing Manager for Ignition Devices, extending his role to all Discrete IGBTs from November 2018 . Before joining Littelfuse he was Product Marketing Manager at Fairchild and application engineer for Electric Vehicles at Infineon Technologies. From 2007 to 2011 he worked at AICIA, a research institute in Andalusia, Spain, dealing with power electronic converters for grid efficiency improvement. Jose is based in Valencia, Spain, and can be reached at [email protected].


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Understanding Littelfuse Ignition IGBTs Datasheets/media/electronics/application_notes/... · Ignition IGBTs Datasheets 2019 Littelfuse Littelfuse.com The Challenge During the design