LITTELFUSE 0437.750WR

Surface Mount Fuses
Ceramic Fuse > 437 Series
437 Series – 1206 Fast-Acting Fuse
Description
This 100% Lead-free, RoHS compliant and Halogen-free
fuse series has been designed specifically to provide over
current protection to circuits that see high working ambient
temperatures (up to 150ºC).
In addition to this, the high I²t values typical of the
Littelfuse Ceramic Fuse family ensure high inrush current
withstand capability.
Features
Agency Approvals
Agency
Agency File Number
Ampere Range
E10480
0.250A ~ 8A
LR29862
0.250A ~ 8A
• Operating Temperature
from -55ºC to +150ºC
• 100% Lead-free and
RoHS compliant
• Suitable for both leaded
and lead-free reflow /
wave soldering
Applications
Electrical Characteristics for Series
• Automotive Electronics
• Printers
% of Ampere
Rating
Ampere Rating
Opening Time at 25ºC
• LCD Displays
• Scanners
100%
250mA - 8A
4 hours, Minimum
• Servers
• Data Modems
250%
750mA - 8A
5 seconds, Maximum
350%
250mA -500mA
5 seconds, Maximum
350%
750mA - 8A
1 second, Maximum
Electrical Specifications by Item
Ampere
Max.
Amp
Rating
Voltage
Code
(A)
Rating (V)
250mA
375mA
500mA
750mA
1A
1.25A
1.5A
1.75A
2A
2.5A
3A
3.5A
4A
5A
7A
8A
.250
.375
.500
.750
001.
1.25
01.5
1.75
002.
02.5
003.
03.5
004.
005.
007.
008.
125
125
63
63
63
63
63
63
63
32
32
32
32
32
32
32
Interrupting Rating
50 A @ 125 V AC/DC
50 A @ 63 V AC/DC
50 A @ 32 V AC/35 V DC
Nominal Nominal Voltage Nominal Power Agency Approvals
Nominal
Dissipation At
Resistance Melting I2t Drop At Rated
(A2Sec.)3
Current (V)4
Rated Current (W)
(Ohms)2
2.290
1.330
0.908
0.665
0.360
0.318
0.209
0.0703
0.058
0.043
0.033
0.027
0.022
0.016
0.010
0.0084
0.003
0.010
0.018
0.064
0.100
0.256
0.324
0.075
0.144
0.225
0.400
0.576
1.024
1.936
4.900
6.400
Notes:
1. AC Interrupting Rating tested at rated voltage with unity power factor. DC Interrupting
Rating tested at rated voltage with time constant < 0.8 msec.
2.Nominal Resistance measured with < 10% rated current.
3.Nominal Melting I²t measured at 1 msecs. opening time.
4.Nominal Voltage Drop measured at rated current after temperature has stabilized.
© 2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/437.html for current information.
0.78
0.60
0.52
0.45
0.41
0.40
0.39
0.27
0.17
0.14
0.15
0.16
0.16
0.09
0.11
0.067
0.195
0.225
0.260
0.335
0.415
0.496
0.579
0.474
0.345
0.363
0.462
0.560
0.618
0.484
0.760
0.539
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Devices designed to carry rated current for 4 hours minimum. It is recommended that
devices be operated continuously at no more than 80% rated current. See “Temperature
Rerating Curve”for additional rerating information.
Devices designed to be mounted with marking code facing up.
17
Revised: June 23, 2011
437 Series
437 Series
The general design ensures excellent temperature stability
and performance reliability.
Mount
Fuses
IntroductionSurface
to Circuit
Protection
Ceramic FuseTransientology
> 437 Series
7A
8A
120
10
100
80
TIME IN SECONDS
PERCENT OF RATING
.750A
1A
1.25
1.5A
1.75
2A
2.5A
3A
3.5A
4A
5A
100
140
.375A
.500A
Average Time Current Curves
.250A
Temperature Rerating Curve
60
40
-65
-45
-25
-5
15
35
55
75
95
115
135
155
TEMPERATURE (°C)
Note:
1
0.1
0.01
1. Rerating depicted in this curve is in addition to the standard rerating of 20% for
continuous operation.
Example:
For continuous operation at 75 degrees celsius, the fuse should be rerated as follows:
I = (0.80)(0.85)IRAT = (0.68)IRAT
0.001
1
0.1
10
100
CURRENT IN AMPERES
Soldering Parameters
Pb – free assembly
Pre Heat
- Temperature Min (Ts(min))
150°C
- Temperature Max (Ts(max))
200°C
- Time (Min to Max) (ts)
60 – 180 seconds
Average Ramp-up Rate (Liquidus Temp
(TL) to peak)
3°C/second max.
TS(max) to TL - Ramp-up Rate
5°C/second max.
Reflow
- Temperature (TL) (Liquidus)
217°C
- Temperature (tL)
60 – 150 seconds
Peak Temperature (TP)
260+0/-5 °C
Time within 5°C of actual peak
Temperature (tp)
10 – 30 seconds
Ramp-down Rate
6°C/second max.
Time 25°C to peak Temperature (TP)
8 minutes max.
Do not exceed
260°C
Wave Soldering
437 Series
tP
TP
Critical Zone
TL to TP
Ramp-up
TL
TS(max)
Temperature
Reflow Condition
tL
Ramp-down
TS(min)
25
Preheat
tS
time to peak temperature
(t 25ºC to peak)
Time
260°C, 10 seconds max.
18
© 2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/437.html for current information.
Surface Mount Fuses
Ceramic Fuse > 437 Series
Product Characteristics
Materials
Moisture
IPC/JEDEC J-STD-020C, Level 1
Sensitivity Level
Solderability
IPC/EIC/JEDEC J-STD-002B, Condition B
Humidity Test
MIL-STD-202, Method 103B, Conditions D
Resistance to
Solder Heat
MIL-STD-202, Method 210F, Condition B
Dimensions
Moisture Resistance
MIL-STD-202, Method 106G
Thermal Shock
MIL-STD-202, Method 107G,
Condition B
Mechanical Shock
MIL-STD-202, Method 213B,
Condition A
Vibration
MIL-STD-202, Method 201A
Vibration,
High Frequency
MIL-STD-202, Method 204D,
Condition D
Dissolution of
Metallization
IPC/EIC/JEDEC J-STD-002B,
Condition D
Terminal Strength
IEC 60127-4
437 Series
Body: Advanced Ceramic
Terminations: A
g / Ni / Sn (100% Lead-free)
Element Cover Coating: Lead-free Glass
Part Marking System
1.000
[0.039]
1.63 +0.10 / -0.2
[0.064 +0.004 / -0.008]
3.200 ± 0.1778
[0.126 ± 0.007]
Amp Code
Marking Code
.250
D
.375
E
.500
F
.750
G
001.
H
N
0.8179 +0.046 / -0.076
[0.0332 +0.0018 / -0.003]
2
1.25
J
01.5
K
1.75
L
002.
N
02.5
O
003.
P
03.5
R
004.
S
005.
T
007.
W
008.
X
0.520 ± 0.200
[0.020 ± 0.08]
1.000
[0.039]
Part Numbering System
1.500
[0.059]
0437 008. W R
SERIES
1.800
[0.071]
packing Code
R = Reel Pack
Amp code
3.500
[0.138]
quantity code
W = 3000 pcs
Packaging
Packaging Option
Packaging Specification
Quantity
Quantity &
Packaging Code
8mm Tape and Reel
EIA-481, IEC 60286, Part 3
3000
WR
© 2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/437.html for current information.
19
437 Series