ICP-S ROHM Electronics, ICP-S Datasheet - Page 10

• Manufacturer Part Number: ICP-S
• Description: Overcurrent Protection Elements
• Manufacturer: ROHM Electronics

Overcurrent Protection Elements
Joule Integral Calculation of Irregularly Increasing or Decreasing Current
Current mode: Irregular wave form + triangular wave form
Model: ICP-S1.2
Wave form:
Wave form approximation: The above wave form (electric charge wave form) is approximated as an
Test:
Plotting test:
Test results: The steady-state current is between lines B and A. Therefore, it is considered that the
Actual wave form
Item Peak
No.
ICP-S will deteriorate or break the current due to the repetitive pulses.
1
2
3
4
5
current
(A)
3.5
Im
10
8
6
2
10A
Segmented
0.1ms
(ms)
0.06
0.35
0.25
0.55
8A
period
irregular wave form to calculate the Joule integral of the wave form.
0.1
t
100000
10000
1000
6A
100
0.1
0.001
10
1
10×8×0.06+1/3×(10−8)
8×6×0.1+1/3×(8−6)
6×3.5×0.35+1/3×(6−3.5)
3.5×2×0.25+1/3×(3.5−2)
1/3×(2)
0.35ms
1
Ta=25°C
0.01
2
A : Effective pulse breaking
I
2
3
2
t-t Characteristic Curve
line (with no margin)
×0.55=
0.1
3.5A
Approximation curve for Joule
integral calculation
4
Coefficient × Im
0.25ms
1
Time (msec)
5
C : Effective pulse recommended
2
×0.1=
Joule integral
line (with margin)
10
2A
2
Formula
×0.06=
2
2
×0.35=
×0.25=
100
B : Effective pulse critical
(ICP-S1.2)
2
line (with no margin)
0.55ms
× t A
1000
ICP-S Technical Manual
2
10000
•
ms)
100000
4.88
4.93
8.07
1.93
0.73
Rev.A
Accumu-
(A
17.88
19.81
20.54
lation
4.88
9.81
2
•
ms)
Lapsed
(ms)
0.06
0.16
0.51
0.76
1.31
time
10/13