ROHM ICP-S

ICP-S Technical Manual
Overcurrent Protection Elements
ICP-S Technical Manual
ICP-S
1. Overview
The ICP-S is an IC protector of surface mounting type developed as an element for the protection of ICs from output
short-circuiting damage. The internal resistance of this lightweight, compact overcurrent protection element is low, as long
as the steady-state current of the element does not exceed the rated DC or AC current. The ICP-S, however, turns off ICs
instantly if the steady-state current reaches or exceeds the breaking current of the ICP-S.
2. External Dimensions (Unit: mm)
4.0±0.1
1.55±0.1
2.0±0.1
0.6
1.0
1.8±0.1
TN direction
φ1.15±0.1
2.8±0.2
0.4±0.1
1.75±0.1
3.5±0.05
2.0±0.05
3.5±0.2
5.3±0.2
2.5±0.1
3.2±0.2
0~0.1
+0.1
−0
8.0±0.2
φ1.5
4.0±0.1
0~0.5
3.0±0.1
2.3±0.2
(Mark: TN)
3. Features
1) Instantly breaks currents with a low potential drop.
(See 3-1 Potential Drop Comparison)
2) Compact surface-mounting model.
(See 2. External Dimensions)
3) Unlike fuses, there is no steady-state current reduction with the rated current applied. No derating is necessary.
4) Minimal breaking point dispersion.
(See the graph in 3-2 Breaking Current Dispersion
Characteristics)
5) Excellent temperature characteristics
(See the graphs in 3-3 Temperature Characteristics)
• The fluctuation of the breaking current caused by temperature changes is minimal.
• Wide operating temperature range: −55°C to +125°C
6) Excellent vibration resistance.
7) UL-approved product with certification No. 107856.
8) No deterioration or circuit breaking caused by static electricity.
Rev.A
1/13
ICP-S Technical Manual
Overcurrent Protection Elements
3-1 Potential Drop Comparison (ICP-S VS Fuse)
ICP-S1.0 (Rated Current: 1 A)
2.0A
1.8A
1.5A
+
1.0A
DC
500mV / div
NORMAL
10mSEC / div
Fuse (Rated Current: 1 A)
4.0A
3.0A
2.0A
1.0A
+
DC
500mV / div
NORMAL
10mSEC / div
Rev.A
2/13
ICP-S Technical Manual
Overcurrent Protection Elements
3-2 Breaking Current Dispersion Characteristics
1000
Breaking time (mec)c
100
10
typ
max
min
n=5pcs×5lot
1
0.1
0.01
0 1 2 3 4
5 6 7 8
9 10 11 12 13 14 15 16 17 18 19 20
Breaking Current (A)
Breaking Time (Reference) Effective Value and Dispersion Data (ICP-S1.0)
1.2
3.0
1.1
2.5
Current applied (A)
Breaking current ratio
3-3 Temperature Characteristics
1.0
0.9
0.8
2.0
1.5
1.2
1.0
0.7
0.7
0
−50
0.5
−25
0
25
50
75
100
125
0
0
S1.2
S1.0
S0.7
S0.5
25
50
75
100
125
150
Ambient temperature Ta (°C)
Ambient temperature Ta (°C)
Breaking Current vs.
Ambient Temperature Characteristics (ICP-S)
Rated Current Derating Curve (ICP-S)
Rev.A
175
3/13
ICP-S Technical Manual
Overcurrent Protection Elements
4. Selection Flowchart
Type of steady-state current?
DC
Pulse
Surge current Inrush current
included
included
Check with the I2t characteristics graph.
Does the steady-state
current not exceed the rated
current of the ICP?
No
Change the ICP model
to satisfy the condition.
Yes
Is the rated voltage (i.e., the
open-circuit voltage when the ICP
breaks the current) 50 V or below?
Yes
Lower the
open-circuit voltage.
No
Is the breaking current (the maximum
abnormal current) within a range
of 2x to 10x of the ICP's rated current?
Yes
Change the ICP model to
satisfy the condition.
No
The selection is OK.
List of ICP-S Models
TYPE
Rated current (A)
0.5
ICP-S0.5
0.7
ICP-S0.7
1.0
ICP-S1.0
1.2
ICP-S1.2
Breaking current (A)
1.0 to 5.0
1.4 to 7.0
2.0 to 10.0
2.4 to 12.0
The I2t-t characteristic graph (i.e., the Joule integral sheet) provides necessary data used to check
how the life of the ICP-S is influenced by heat cycling or mechanical fatigue caused by repetitive
current pulses.
Rev.A
4/13
ICP-S Technical Manual
Overcurrent Protection Elements
5. Checks with I2t-tCharacteristic Graph
If the steady-state current includes a pulse, surge, or inrush-current, use the I2t
graph and check that the ICP will not deteriorate regardless of the mode of the
current or the ICP will not break the steady-state current while the ICP is in operation.
I2t-t Graph
I2t-t Graph
I2 t (A2 - ms)
Breaking
current area
Deterioration
area
Safety area
Margin area
t (s)
Breaking current area: The ICP breaks the current in this area.
Deterioration area: Although the ICP does not break the current instantaneously,
the ICP may break the current as a result of ICP deterioration.
Marginal area: The area where the risk of ICP deterioration is low.
Basically avoid using this area.
Safety area: The ICP will not deteriorate or break the current.
Precautions
• Even though the Joule integral value of the current wave form designed at your end is
within the safety area, it is recommended that you confirm the steady-state current for
the safety of the components
Refer to the next section, calculate the I2t value, and check the position of the I2t value
in the graph. If the value is in the safety area, it is okay to use the selected ICP model.
If the value is, however, beyond the safety area, use an ICP model with higher ratings.
• Note: The inspection and selection of the ICP according to the Joule integral value is
absolutely based on the results of the approximation of the current wave form.
Be sure to inspect all the current wave forms of your application, or otherwise the safety
of the application will not be fully ensured.
• Consider a safety margin with the dispersion of component characteristics taken into
calculation when inspecting and selecting the ICP, if it is impossible to check the worst
current wave form.
Rev.A
5/13
ICP-S Technical Manual
Overcurrent Protection Elements
6. I2t Calculation of a Variety of Wave forms
If the steady-state current includes a pulse, surge, or inrush current, calculate the I2t of
the wave form of the current. The following graphs and formulas show how to calculate
a variety of wave forms.
1) Triangular
wave form
Im
0
2) Rectangular
wave form
0
I2t = 1 Im2t
3
t
Im
I2t = Im2t
t
3) Irregular
wave form
I2
0
4) Charged or
discharged
wave form
I1
I2t = I1I2t + 1 (I1 − I2)2t
3
t
• The charged wave form is segmented as shown below. The Joule heat
generated during each segmented period is plotted onto a Joule integral
sheet.
Segments 1 through 4 are treated as
irregular wave forms and calculated,
while segment 5 is treated as a
triangular wave form and calculated.
1
2
3
4
5
Rev.A
6/13
ICP-S Technical Manual
Overcurrent Protection Elements
7. ICP-S Test Example
7-1 Example 1
Current mode: DC
Model: ICP-S1.0
Wave form:
DC
1A
2A
5A
Test:
The current values of all segmented periods are plotted respectively as shown in attached graph 1.
1 A: The steady-state current is in the safety area where the ICP-S will not deteriorate or break the current.
2 A: The ICP-S will break the steady-state current in the breaking current area in approximately 100 ms.
5 A: The ICP-S will break the steady-state current in the breaking current area in approximately 0.7 ms.
7-2 Example 2
Current mode: A single pulse
Model: ICP-S1.0
Wave form: A current of 1.75 A flows for a period of 20 ms.
1.75A
20ms
Results: The steady-state current is in the critical area. If the single pulse is repeated intermittently,
the ICP-S will deteriorate or break the current in the end.
Test:
With pulse current: I2t = 1.752×20
= 61 (A2 • ms)
at 20ms
(See graph 2)
Rev.A
7/13
ICP-S Technical Manual
Overcurrent Protection Elements
10000
Graph 1
Ta=25°C
I2 t (A2 - ms)
1000
100
A :Effective pulse breaking
line (with no margin)
10
B :Effective pulse critical line
(with no margin)
C :Effective pulse recommended
critical line (with margin)
DC
1A
DC
0.1
2A
DC
5A
1
0.01
0.001
0.01
0.1
1
10
100
1000
10000
100000
Time (msec)
I2 t-t Characteristic Curve (ICP-S1.0)
10000
Graph 2
Ta=25°C
I2 t (A2 - ms)
1000
100
61 (A2 ms) at 20ms
A :Effective pulse breaking
line (with no margin)
10
B :Effective pulse critical line
(with no margin)
C :Effective pulse recommended
critical line (with margin)
1
0.1
0.01
0.001
0.01
0.1
1
10
100
1000
10000
100000
Time (msec)
I2 t-t Characteristic Curve (ICP-S1.0)
Rev.A
8/13
ICP-S Technical Manual
Overcurrent Protection Elements
Joule Integral Calculation of Irregularly Increasing or Decreasing Current
Current mode: Irregular triangular wave form
Model: ICP-S1.0
Wave form:
3A
Approximation curve for
Joule integral calculation
Actual wave form
1ms
Wave form approximation: The above wave form is approximated by electrically calculating the Joule
integral of each segment of the current wave form. In consideration of the heat
cycling and mechanical fatigue of the ICP-S, however, a practical Joule
integral value is calculated from an approximation curve obtained by
connecting the peak of each current wave form.
Test: Obtain the approximated value by substituting the values into the formula
(triangular wave form I2t = 1/3 • Im2 • t).
I2t = 1/3 × 32A × 1ms = 3 (A2 • ms)
Plotting test:
10000
Graph 2
Ta=25°C
I2 t (A2 - ms)
1000
100
A :Effective pulse breaking
line (with no margin)
10
B: Effective pulse critical line
(with no margin)
3 (A2 ms) at 1ms
C: Effective pulse recommended
critical line (with margin)
1
0.1
0.01
0.001
0.01
0.1
1
10
100
1000
10000
100000
Time (msec)
I2 t-t Characteristic Curve (ICP-S1.0)
Test results: The steady-state current does not exceed line C. Therefore, it is considered that the ICP-S
will not deteriorate or break the current.
Rev.A
9/13
ICP-S Technical Manual
Overcurrent Protection Elements
Joule Integral Calculation of Irregularly Increasing or Decreasing Current
Current mode: Irregular wave form + triangular wave form
Model: ICP-S1.2
10A
Wave form:
8A
Actual wave form
Approximation curve for Joule
integral calculation
6A
3.5A
2A
0.06ms
0.1ms
0.35ms
0.25ms
0.55ms
Wave form approximation: The above wave form (electric charge wave form) is approximated as an
irregular wave form to calculate the Joule integral of the wave form.
Test:
Accumu- Lapsed
Peak Segmented
Item current
Joule integral
period
lation
time
Formula
Im
t
No.
Coefficient × Im2 × t A2 • ms)
(A)
(ms)
(A2 • ms) (ms)
2
1
10
0.06 10×8×0.06+1/3×(10−8) ×0.06=
4.88
0.06
4.88
0.1 8×6×0.1+1/3×(8−6)2×0.1=
4.93
0.16
9.81
8
2
8.07
0.51
17.88
6
3
0.35 6×3.5×0.35+1/3×(6−3.5)2×0.35=
1.93
0.76
19.81
3.5
4
0.25 3.5×2×0.25+1/3×(3.5−2)2×0.25=
0.73
1.31
20.54
2
5
0.55 1/3×(2)2×0.55=
Plotting test:
100000
Ta=25°C
10000
I2 t (A2 - ms)
A : Effective pulse breaking
line (with no margin)
5
4
1000
3
100
10
2
1
B : Effective pulse critical
line (with no margin)
1
C : Effective pulse recommended
line (with margin)
0.1
0.001
0.01
0.1
1
10
100
1000
10000
100000
Time (msec)
I2 t-t Characteristic Curve (ICP-S1.2)
Test results: The steady-state current is between lines B and A. Therefore, it is considered that the
ICP-S will deteriorate or break the current due to the repetitive pulses.
Rev.A
10/13
ICP-S Technical Manual
Overcurrent Protection Elements
8. Application Circuit Example
8-1 Recommended Flow Soldering Conditions
(°C)
Preheating
Soldering
Natural cooling
300
260°C
Solder temperature
250
230°C
200
Manual soldering conditions
Soldering iron temperature: 350°C max.
150
Soldering time: 3 seconds max.
120°C
100
100°C
50
25
2 minutes min.
10 seconds min.
1 minute min.
5 minutes min.
8-2 Recommended Reflow Soldering Conditions
Peak temperature
(°C)
230 to 260°C, 10sec Max.
250
Reflow heating temperature
1 to 5°C / sec
Temperature
200
150
100
Preheating
120 to 160°C,
50 to 120 sec
50
0
Reflow soldering
(High-temperature
retention time)
200°C,
30 to 60 sec
Preheating
speed
1 to 5°C / sec
Cooling
60sec Min.
∗ Number of reflow times: 2 TIMES Max.
A peak temperature of at least 230°C is recommended. If the peak temperature is less than 230°C, it is recommended to
make some adjustments, such as the retention of the peak temperature and soldering time longer and an increase in the thickness
of solder paste.
1.8 to 2.4
8-3 Recommended Copper Pattern on PCB
1.6 to 2.0
4.0 to 5.0
Rev.A
11/13
ICP-S Technical Manual
Overcurrent Protection Elements
9. Application Circuit Examples
9-1 Power Supply Circuit
ICP
9-2 DC-DC Converter
ICP
ICP
9-3 Motor Control
VCC
ICP
M
Rev.A
12/13
ICP-S Technical Manual
Overcurrent Protection Elements
10. Precautions
1. Set the breaking current two to ten times as high as the rated current.
Use the ICP-S so that the open-circuit voltage between the terminals after the ICP-S breaks
the current will be a maximum of 50 V. Unless the ICP-S is used under these conditions, the
mold may be damaged or internal resistance may remain after the ICP-S breaks the current.
2. Do not use the ICP-S for the primary side of commercial power supply, or otherwise the mold
may be damaged by arcing after the ICP-S breaks the current.
10000
10000
Ta=25°C
1000
1000
100
100
I2 t (A2 - ms)
I2 t (A2 - ms)
Ta=25°C
10
A :Effective pulse breaking
line (with no margin)
10
A :Effective pulse breaking
line (with no margin)
B: Effective pulse critical line
(with no margin)
1
B: Effective pulse critical line
(with no margin)
1
C: Effective pulse recommended
critical line (with margin)
C: Effective pulse recommended
critical line (with margin)
0.1
0.01
0.001
0.01
0.1
1
0.1
10
100
1000
10000
0.01
0.001
100000
0.1
1
10
100
1000
10000
Time (msec)
Time (msec)
I2 t-t Characteristic Curve (ICP-S0.5)
I2 t-t Characteristic Curve (ICP-S0.7)
10000
100000
10000
Ta=25°C
Ta=25°C
1000
1000
100
100
I2 t (A2 - ms)
I2 t (A2 - ms)
0.01
A :Effective pulse breaking
line (with no margin)
10
B: Effective pulse critical line
(with no margin)
1
A :Effective pulse breaking
line (with no margin)
10
B: Effective pulse critical line
(with no margin)
1
C: Effective pulse recommended
critical line (with margin)
C: Effective pulse recommended
critical line (with margin)
0.1
0.01
0.001
0.1
0.01
0.1
1
10
100
1000
10000
100000
0.01
0.001
0.01
0.1
1
10
100
1000
10000
Time (msec)
Time (msec)
I2 t-t Characteristic Curve (ICP-S1.0)
I2 t-t Characteristic Curve (ICP-S1.2)
Rev.A
100000
13/13
Appendix
Notes
No technical content pages of this document may be reproduced in any form or transmitted by any
means without prior permission of ROHM CO.,LTD.
The contents described herein are subject to change without notice. The specifications for the
product described in this document are for reference only. Upon actual use, therefore, please request
that specifications to be separately delivered.
Application circuit diagrams and circuit constants contained herein are shown as examples of standard
use and operation. Please pay careful attention to the peripheral conditions when designing circuits
and deciding upon circuit constants in the set.
Any data, including, but not limited to application circuit diagrams information, described herein
are intended only as illustrations of such devices and not as the specifications for such devices. ROHM
CO.,LTD. disclaims any warranty that any use of such devices shall be free from infringement of any
third party's intellectual property rights or other proprietary rights, and further, assumes no liability of
whatsoever nature in the event of any such infringement, or arising from or connected with or related
to the use of such devices.
Upon the sale of any such devices, other than for buyer's right to use such devices itself, resell or
otherwise dispose of the same, no express or implied right or license to practice or commercially
exploit any intellectual property rights or other proprietary rights owned or controlled by
ROHM CO., LTD. is granted to any such buyer.
Products listed in this document are no antiradiation design.
The products listed in this document are designed to be used with ordinary electronic equipment or devices
(such as audio visual equipment, office-automation equipment, communications devices, electrical
appliances and electronic toys).
Should you intend to use these products with equipment or devices which require an extremely high level of
reliability and the malfunction of with would directly endanger human life (such as medical instruments,
transportation equipment, aerospace machinery, nuclear-reactor controllers, fuel controllers and other
safety devices), please be sure to consult with our sales representative in advance.
About Export Control Order in Japan
Products described herein are the objects of controlled goods in Annex 1 (Item 16) of Export Trade Control
Order in Japan.
In case of export from Japan, please confirm if it applies to "objective" criteria or an "informed" (by MITI clause)
on the basis of "catch all controls for Non-Proliferation of Weapons of Mass Destruction.
Appendix1-Rev1.1