Low Loss Duopack: IGBT 7 with Trench and Fieldstop technology
Features• VCE = 650 V• IC = 75 A• Very Low VCEsat
• Low turn-off losses• Short tail current• Reduced EMI• Humidity robust design• Very soft, fast recovery antiparallel diode• Maximum junction temperature Tvjmax = 175°C• Qualified according to JEDEC for target applications• Pb-free lead plating; RoHS compliant• Complete product spectrum and PSpice Models: http://www.infineon.com/igbt7/Potential applications• Servo Drives• General Purpose Drives (GPD)• Industrial UPS• Industrial SMPS• Solar Optimizer• Solar String InverterProduct validation• Product Validation: Qualified for industrial applications according to the relevant tests of
JEDEC47/20/22
GC
E
DescriptionPackage pin definition:• Pin C & backside - Collector• Pin E - Emitter• Pin G - Gate
G
C
E
Type Package MarkingIKW75N65ET7 PG-TO247-3 K75EET7
IKW75N65ET7Low Loss Duopack: IGBT 7
Datasheet Please read the Important Notice and Warnings at the end of this document 1.00www.infineon.com 2021-06-29
Table of contents
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Potential applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Product validation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Table of contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1 Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 IGBT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
3 Diode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
4 Characteristics diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5 Package outlines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
6 Testing conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Disclaimer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
IKW75N65ET7Low Loss Duopack: IGBT 7
Table of contents
Datasheet 2 1.002021-06-29
1 Package
Table 1 Characteristic values
Parameter Symbol Note or test condition Values Unit
Min. Typ. Max.
Internal emitter inductancemeasured 5 mm (0.197 in)from case
LE 13.0 nH
Storage temperature Tstg -55 150 °C
Soldering temperature wave soldering 1.6 mm (0.063 in.) from casefor 10 s
260 °C
Mounting torque, M3 screwMaximum of mountingprocesses: 3
M 0.6 Nm
Thermal resistance,junction-ambient
Rth(j-a) 40 K/W
2 IGBT
Table 2 Maximum rated values
Parameter Symbol Note or test condition Values Unit
Collector-emitter voltage VCE Tvj ≥ 25 °C 650 V
DC collector current, limitedby Tvjmax
IC limited by bondwire TC = 25 °C 80 A
TC = 100 °C 78.5
Pulsed collector current, tplimited by Tvjmax 1)
ICpuls 225 A
Turn-off safe operatingarea2)
VCE ≤ 650 V, tP = 1 µs, Tvj ≤ 175 °C 225 A
Gate-emitter voltage VGE ±20 V
Transient gate-emittervoltage
VGE tp ≤ 10 µs, D < 0.010 ±30 V
Short circuit withstand time tSC VGE = 15 V, Allowednumber of short circuits< 1000, Time betweenshort circuits ≥ 1.0 s
VCC ≤ 330 V,Tvj = 100 °C
5 µs
VCC ≤ 400 V,Tvj = 150 °C
3
Power dissipation Ptot TC = 25 °C 333 W
TC = 100 °C 167
1) Defined by design. Not subject to production test.2) Clamped inductive load current test for each device, IC=225A, VCC=400V, Tc=25°C, VGE=20V, L=80µH, RG=10Ω
IKW75N65ET7Low Loss Duopack: IGBT 7
1 Package
Datasheet 3 1.002021-06-29
Table 3 Characteristic values
Parameter Symbol Note or test condition Values Unit
Min. Typ. Max.
Collector-emitter saturationvoltage
VCE sat IC = 75.0 A, VGE = 15 V Tvj = 25 °C 1.35 1.65 V
Tvj = 125 °C 1.50
Tvj = 175 °C 1.60
Gate-emitter thresholdvoltage
VGEth IC = 0.75 mA, VCE = VGE 4.30 5.00 5.70 V
Zero gate voltage collectorcurrent
ICES VCE = 650 V, VGE = 0 V Tvj = 25 °C 40 µA
Tvj = 175 °C 1200
Gate-emitter leakage current IGES VCE = 0 V, VGE = 20 V 100 nA
Transconductance gfs IC = 75.0 A, VCE = 20 V 40 S
Short circuit collectorcurrent
ISC VGE = 15 V, tSC ≤ 3 µs, Allowed number ofshort circuits < 1000 , Time between shortcircuits ≥ 1.0 s
350 A
Input capacitance Cies VCE = 25 V, VGE = 0 V, f = 1000 kHz 4460 pF
Output capacitance Coes VCE = 25 V, VGE = 0 V, f = 1000 kHz 135 pF
Reverse transfer capacitance Cres VCE = 25 V, VGE = 0 V, f = 1000 kHz 46 pF
Gate charge QG IC = 75.0 A, VGE = 15 V, VCE = 520 V 435 nC
Turn-on delay time tdon VCE = 400 V, VGE = 15 V,RGon = 4.7 Ω,RGoff = 4.7 Ω, Lσ = 32 nH,Cσ = 30 pF
Tvj = 25 °C,IC = 75.0 A
28 ns
Tvj = 25 °C,IC = 37.5 A
26
Tvj = 175 °C,IC = 75.0 A
31
Tvj = 175 °C,IC = 37.5 A
28
Rise time (inductive load) tr VCE = 400 V, VGE = 15 V,RGon = 4.7 Ω,RGoff = 4.7 Ω, Lσ = 32 nH,Cσ = 30 pF
Tvj = 25 °C,IC = 75.0 A
25 ns
Tvj = 25 °C,IC = 37.5 A
13
Tvj = 175 °C,IC = 75.0 A
30
Tvj = 175 °C,IC = 37.5 A
18
IKW75N65ET7Low Loss Duopack: IGBT 7
2 IGBT
Datasheet 4 1.002021-06-29
Table 3 Characteristic values (continued)
Parameter Symbol Note or test condition Values Unit
Min. Typ. Max.
Turn-off delay time tdoff VCE = 400 V, VGE = 15 V,RGon = 4.7 Ω,RGoff = 4.7 Ω, Lσ = 32 nH,Cσ = 30 pF
Tvj = 25 °C,IC = 75.0 A
310 ns
Tvj = 25 °C,IC = 37.5 A
330
Tvj = 175 °C,IC = 75.0 A
365
Tvj = 175 °C,IC = 37.5 A
415
Fall time (inductive load) tf VCE = 400 V, VGE = 15 V,RGon = 4.7 Ω,RGoff = 4.7 Ω, Lσ = 32 nH,Cσ = 30 pF
Tvj = 25 °C,IC = 75.0 A
15 ns
Tvj = 25 °C,IC = 37.5 A
11
Tvj = 175 °C,IC = 75.0 A
25
Tvj = 175 °C,IC = 37.5 A
20
Turn-on energy Eon VCE = 400 V, VGE = 15 V,RGon = 4.7 Ω,RGoff = 4.7 Ω, Lσ = 32 nH,Cσ = 30 pF
Tvj = 25 °C,IC = 75.0 A
2.17 mJ
Tvj = 25 °C,IC = 37.5 A
0.79
Tvj = 175 °C,IC = 75.0 A
3.45
Tvj = 175 °C,IC = 37.5 A
1.52
Turn-off energy Eoff VCE = 400 V, VGE = 15 V,RGon = 4.7 Ω,RGoff = 4.7 Ω, Lσ = 32 nH,Cσ = 30 pF
Tvj = 25 °C,IC = 75.0 A
1.23 mJ
Tvj = 25 °C,IC = 37.5 A
0.56
Tvj = 175 °C,IC = 75.0 A
2.05
Tvj = 175 °C,IC = 37.5 A
1.11
IKW75N65ET7Low Loss Duopack: IGBT 7
2 IGBT
Datasheet 5 1.002021-06-29
Table 3 Characteristic values (continued)
Parameter Symbol Note or test condition Values Unit
Min. Typ. Max.
Total switching energy Ets VCE = 400 V, VGE = 15 V,RGon = 4.7 Ω,RGoff = 4.7 Ω, Lσ = 32 nH,Cσ = 30 pF
Tvj = 25 °C,IC = 75.0 A
3.40 mJ
Tvj = 25 °C,IC = 37.5 A
1.35
Tvj = 175 °C,IC = 75.0 A
5.50
Tvj = 175 °C,IC = 37.5 A
2.63
IGBT thermal resistance,junction-case
Rthjc 0.45 K/W
Operating junctiontemperature
Tvj -40 175 °C
Note: Electrical Characteristic, at Tvj=25°C, unless otherwise specified.
3 Diode
Table 4 Maximum rated values
Parameter Symbol Note or test condition Values Unit
Repetitive peak reversevoltage
VRRM Tvj ≥ 25 °C 650 V
Diode forward current,limited by Tvjmax
IF limited by bondwire TC = 25 °C 80 A
TC = 100 °C 74
Diode pulsed current,limited by Tvjmax 1)
IFpuls 225 A
1) Defined by design. Not subject to production test.
Table 5 Characteristic values
Parameter Symbol Note or test condition Values Unit
Min. Typ. Max.
Diode forward voltage VF IF = 75.0 A Tvj = 25 °C 1.65 2.00 V
Tvj = 125 °C 1.60
Tvj = 175 °C 1.55
Reverse leakage current IR VR = 650 V Tvj = 25 °C 40 µA
Tvj = 175 °C 1200
IKW75N65ET7Low Loss Duopack: IGBT 7
3 Diode
Datasheet 6 1.002021-06-29
Table 5 Characteristic values (continued)
Parameter Symbol Note or test condition Values Unit
Min. Typ. Max.
Diode reverse recovery time trr VR = 400 V Tvj = 25 °C,IF = 75.0 A,-diF/dt = 1650 A/µs
100 ns
Tvj = 25 °C,IF = 37.5 A,-diF/dt = 2725 A/µs
70
Tvj = 175 °C,IF = 75.0 A,-diF/dt = 1650 A/µs
155
Tvj = 175 °C,IF = 37.5 A,-diF/dt = 2260 A/µs
125
Diode reverse recoverycharge
Qrr VR = 400 V Tvj = 25 °C,IF = 75.0 A,-diF/dt = 1650 A/µs
1.50 µC
Tvj = 25 °C,IF = 37.5 A,-diF/dt = 2725 A/µs
1.15
Tvj = 175 °C,IF = 75.0 A,-diF/dt = 1650 A/µs
4.40
Tvj = 175 °C,IF = 37.5 A,-diF/dt = 2260 A/µs
3.36
Diode peak reverse recoverycurrent
Irrm VR = 400 V Tvj = 25 °C,IF = 75.0 A,-diF/dt = 1650 A/µs
22.0 A
Tvj = 25 °C,IF = 37.5 A,-diF/dt = 2725 A/µs
34.0
Tvj = 175 °C,IF = 75.0 A,-diF/dt = 1650 A/µs
41.0
Tvj = 175 °C,IF = 37.5 A,-diF/dt = 2260 A/µs
43.0
IKW75N65ET7Low Loss Duopack: IGBT 7
3 Diode
Datasheet 7 1.002021-06-29
Table 5 Characteristic values (continued)
Parameter Symbol Note or test condition Values Unit
Min. Typ. Max.
Diode peak rate off fall ofreverse recovery current
dIrr/dt VR = 400 V Tvj = 25 °C,IF = 75.0 A,-diF/dt = 1650 A/µs
-480 A/µs
Tvj = 25 °C,IF = 37.5 A,-diF/dt = 2725 A/µs
-600
Tvj = 175 °C,IF = 75.0 A,-diF/dt = 1650 A/µs
-590
Tvj = 175 °C,IF = 37.5 A,-diF/dt = 2260 A/µs
-500
Diode thermal resistance,junction-case
Rthjc 0.60 K/W
Operating junctiontemperature
Tvj -40 175 °C
Note: For optimum lifetime and reliability, Infineon recommends operating conditions that do not exceed 80% ofthe maximum ratings stated in this datasheet.
IKW75N65ET7Low Loss Duopack: IGBT 7
3 Diode
Datasheet 8 1.002021-06-29
4 Characteristics diagrams
Power dissipation as a function of case temperature,IGBTPtot = f(Tc)Tvj ≤ 175 °C
Collector current as a function of case temperature,IGBTIC = f(Tc)Tvj ≤ 175 °C, VGE ≥ 15 V
25 50 75 100 125 150 1750
50
100
150
200
250
300
350
25 50 75 100 125 150 1750
10
20
30
40
50
60
70
80
90
Typical output characteristic, IGBTIC = f(VCE)Tvj = 25 °C
Typical output characteristic, IGBTIC = f(VCE)Tvj = 175 °C
0 1 2 3 4 50
25
50
75
100
125
150
175
200
225
0 1 2 3 4 50
25
50
75
100
125
150
175
200
225
IKW75N65ET7Low Loss Duopack: IGBT 7
4 Characteristics diagrams
Datasheet 9 1.002021-06-29
Typical transfer characteristic, IGBTIC = f(VGE)VCE = 20 V
Typical collector-emitter saturation voltage as afunction of junction temperature, IGBTVCEsat = f(Tvj)VGE = 15 V
2 4 6 8 10 12 140
25
50
75
100
125
150
175
200
225
25 50 75 100 125 150 1750.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Gate-emitter threshold voltage as a function ofjunction temperature, IGBTVGEth = f(Tvj)IC = 0.75 mA
Typical switching times as a function of collectorcurrent, IGBTt = f(IC)VCE = 400 V, Tvj = 175 °C, VGE = 0/15 V, RG = 4.7 Ω
25 50 75 100 125 1500
1
2
3
4
5
6
0 25 50 75 100 125 150 175 200 2251
10
100
1000
IKW75N65ET7Low Loss Duopack: IGBT 7
4 Characteristics diagrams
Datasheet 10 1.002021-06-29
Typical switching times as a function of gate resistor,IGBTt = f(RG)IC = 75.0 A, VCE = 400 V, Tvj = 175 °C, VGE = 0/15 V
Typical switching times as a function of junctiontemperature, IGBTt = f(Tvj)IC = 75.0 A, VCE = 400 V, VGE = 0/15 V, RG = 4.7 Ω
0 5 10 15 20 25 30 35 401
10
100
1000
10000
25 50 75 100 125 150 1751
10
100
1000
Typical switching energy losses as a function ofcollector current, IGBTE = f(IC)VCE = 400 V, Tvj = 175 °C, VGE = 0/15 V, RG = 4.7 Ω
Typical switching energy losses as a function of gateresistor, IGBTE = f(RG)IC = 75.0 A, VCE = 400 V, Tvj = 175 °C, VGE = 0/15 V
0 25 50 75 100 125 150 175 200 2250
5
10
15
20
25
30
35
0 5 10 15 20 25 30 35 400
2
4
6
8
10
12
14
16
IKW75N65ET7Low Loss Duopack: IGBT 7
4 Characteristics diagrams
Datasheet 11 1.002021-06-29
Typical switching energy losses as a function ofjunction temperature, IGBTE = f(Tvj)IC = 75.0 A, VCE = 400 V, VGE = 0/15 V, RG = 4.7 Ω
Typical switching energy losses as a function ofcollector emitter voltage, IGBTE = f(VCE)IC = 75.0 A, Tvj = 175 °C, VGE = 0/15 V, RG = 4.7 Ω
25 50 75 100 125 150 1750
1
2
3
4
5
6
7
200 250 300 350 400 450 5000
1
2
3
4
5
6
7
8
Typical gate charge, IGBTVGE = f(QGE)IC = 75.0 A
Typical capacitance as a function of collector-emittervoltage, IGBTC = f(VCE)f = 1000 kHz, VGE = 0 V
0 100 200 300 400 5000
2
4
6
8
10
12
14
16
0 5 10 15 20 25 3010
100
1000
10000
IKW75N65ET7Low Loss Duopack: IGBT 7
4 Characteristics diagrams
Datasheet 12 1.002021-06-29
Typical short circuit safe operating range as a functionof collector-emitter voltage, IGBTtSC = f(VCE)
Typical short circuit collector current as a function ofgate-emitter voltage, IGBTIC(SC) = f(VGE)VCE = 400 V, Tvj = 150 °C
300 310 320 330 340 350 360 370 380 390 4003.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
8 10 12 14 16 18 200
100
200
300
400
500
600
700
IGBT transient thermal resistance, IGBTZth = f(tp)D = tp/T
Diode transient thermal impedance as a function ofpulse width, DiodeZth = f(tp)D = tp/T
1E-7 1E-6 1E-5 0.0001 0.001 0.01 0.1 10.0001
0.001
0.01
0.1
1
1E-6 1E-5 0.0001 0.001 0.01 0.1 10.001
0.01
0.1
1
IKW75N65ET7Low Loss Duopack: IGBT 7
4 Characteristics diagrams
Datasheet 13 1.002021-06-29
Typical diode forward current as a function of forwardvoltage, DiodeIF = f(VF)
Typical diode forward voltage as a function ofjunction temperature, DiodeVF = f(Tvj)
0.0 0.5 1.0 1.5 2.0 2.5 3.00
20
40
60
80
100
120
140
160
25 50 75 100 125 150 1750.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Typical reverse recovery time as a function of diodecurrent slope, Diodetrr = f(diF/dt)VR = 400 V, IF = 75 A
Typical reverse recovery charge as a function of diodecurrent slope, DiodeQrr = f(diF/dt)VR = 400 V, IF = 75 A
700 900 1100 1300 1500 1700 19000
50
100
150
200
250
300
350
700 900 1100 1300 1500 1700 19000.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
IKW75N65ET7Low Loss Duopack: IGBT 7
4 Characteristics diagrams
Datasheet 14 1.002021-06-29
Typical reverse recovery current as a function of diodecurrent slope, DiodeIrr = f(diF/dt)VR = 400 V, IF = 75 A
Typical diode peak rate of fall of reverse recoverycurrent as a function of diode current slope, DiodedIrr/dt = f(diF/dt)VR = 400 V, IF = 75 A
700 900 1100 1300 1500 1700 19000
5
10
15
20
25
30
35
40
45
50
700 900 1100 1300 1500 1700 1900-800
-700
-600
-500
-400
-300
-200
-100
0
IKW75N65ET7Low Loss Duopack: IGBT 7
4 Characteristics diagrams
Datasheet 15 1.002021-06-29
5 Package outlines
MILLIMETERS
5.44
c
Q
E3
E2
D
E
D1
D2
L1
e
L
S
P
E1
b1
A
A1
b
A2
b2
0.38
6.04
5.35
1.00
3.40
3.85
20.70
13.08
15.50
0.51
3.50
19.80
12.38
1.60
4.70
2.20
1.00
1.50
2.57
0.89
6.30
6.25
17.65
2.60
5.10
14.15
3.70
21.50
16.30
20.40
1.35
4.50
2.41
5.30
2.60
1.40
2.50
3.43
1
REVISION
06
25.07.2018
ISSUE DATE
EUROPEAN PROJECTION
0
SCALE
5mm
DOCUMENT NO.
Z8B00003327
DIMENSIONSMIN. MAX.
3:1
2 3 4
Package Drawing PG-TO247-3
Figure 6
IKW75N65ET7Low Loss Duopack: IGBT 7
5 Package outlines
Datasheet 16 1.002021-06-29
6 Testing conditions
t
a b
td(off) tf trtd(on)
90% IC
10% IC
90% IC
10% VGE
10% IC
t
90% VGE
t
t
90% VGE
VGE(t)
t
t
tt1 t4
2% IC
10% VGE
2% VCE
t2 t3
Et
tV I toff = x x d
1
2
CE C Et
tV I ton = x x d
3
4
CE C
CC
dI /dtF
dI
I,V
Figure A.
Figure B.
Figure C. Definition of diode switchingcharacteristics
Figure E. Dynamic test circuit
Figure D.
I (t)C
Parasitic inductance L ,parasitic capacitor C ,relief capacitor C ,(only for ZVT switching)
ss
r
t t tQ Q Q
rr a b
rr a b
= += +
Qa Qb
V (t)CE
VGE(t)
I (t)C
V (t)CE
Figure 7
IKW75N65ET7Low Loss Duopack: IGBT 7
6 Testing conditions
Datasheet 17 1.002021-06-29
Revision historyDocument revision Date of release Description of changes
V0.1 2019-10-25 Target Data Sheet
V1.1 2020-04-20 Preliminary data sheet
V2.1 2020-05-12 Final data sheet
1.00 2021-06-29 Change of potential applications and new diagram added (tSC asfunction of VCE)
IKW75N65ET7Low Loss Duopack: IGBT 7
Revision history
Datasheet 18 1.002021-06-29
TrademarksAll referenced product or service names and trademarks are the property of their respective owners.
Edition 2021-06-29Published byInfineon Technologies AG81726 Munich, Germany © 2021 Infineon Technologies AGAll Rights Reserved. Do you have a question about anyaspect of this document?Email: [email protected] Document referenceIFX-AAL330-004
IMPORTANT NOTICEThe information given in this document shall in noevent be regarded as a guarantee of conditions orcharacteristics (“Beschaffenheitsgarantie”).With respect to any examples, hints or any typicalvalues stated herein and/or any information regardingthe application of the product, Infineon Technologieshereby disclaims any and all warranties and liabilitiesof any kind, including without limitation warranties ofnon-infringement of intellectual property rights of anythird party.In addition, any information given in this document issubject to customer’s compliance with its obligationsstated in this document and any applicable legalrequirements, norms and standards concerningcustomer’s products and any use of the product ofInfineon Technologies in customer’s applications.The data contained in this document is exclusivelyintended for technically trained staff. It is theresponsibility of customer’s technical departments toevaluate the suitability of the product for the intendedapplication and the completeness of the productinformation given in this document with respect to suchapplication.
Please note that this product is not qualifiedaccording to the AEC Q100 or AEC Q101 documentsof the Automotive Electronics Council.
WARNINGSDue to technical requirements products may containdangerous substances. For information on the typesin question please contact your nearest InfineonTechnologies office.Except as otherwise explicitly approved by InfineonTechnologies in a written document signed byauthorized representatives of Infineon Technologies,Infineon Technologies’ products may not be used inany applications where a failure of the product orany consequences of the use thereof can reasonablybe expected to result in personal injury.