
294
Revised: July 9, 2008
2008 Littelfuse, Inc.
Teccor brand Thyristors
Specications are subject to change without notice.
Please refer to http://www.littelfuse.com for current information.
55 Amp Standard SCRs
Sxx55x Series
Specications are subject to change without notice.
Please refer to http://www.littelfuse.com for current information.
Figure 7: Maximum Allowable Case Temperature
vs. Average On-State Current
Figure 8: Maximum Allowable Ambient Temperature
vs. RMS On-State Current
Figure 9: Maximum Allowable Ambient Temperature
vs. Average On-State Current
70
75
80
85
90
95
100
105
110
115
120
125
130
0
5
10
15
20
25
30
35
40
Average On-State Current [I
T(AVE)] - Amps
Maximum
Allo
w
able
Case
Temper
at
ur
e
(T
C
)-
°C
CURRENT WAVEFORM: Sinusoidal
LOAD: Resistive or Inductive
CONDUCTION ANGLE: 180°
0
20
40
60
80
100
120
0.0
0.5
1.0
1.5
2.0
2.5
RMS On-State Current [I
T(RMS)] - Amps
Maximum
Allo
w
a
ble
Ambient
Temper
at
ur
e
(T
A
)-
°C
CURRENT WAVEFORM: Sinusoidal
LOAD: Resistive or Inductive
CONDUCTION ANGLE: 180°
FREE AIR RATING
0
20
40
60
80
100
120
0.0
0.5
1.0
1.5
Average On-State Current [I
T(AVE)] - Amps
Maximum
Allo
w
able
Ambient
Temper
at
ur
e
(T
A
)-
°C
CURRENT WAVEFORM: Sinusoidal
LOAD: Resistive or Inductive
CONDUCTION ANGLE: 180°
FREE AIR RATING
Figure 10: Peak Capacitor Discharge Current
Figure 11: Peak Capacitor Discharge Current Derating
100
1000
10000
0.5
1.0
10.0
50.0
P
eak
Disc
har
g
e
Cur
rent
(I
TM
)-
Amps
Pulse Current Duration (t
w) - ms
I
TRM
t
W
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0255075
100
125
150
Nor
maliz
ed
P
eak
Cur
rent
Case Temperature (T
C) - °C
Note: xx = voltage