Littelfuse 438 Series User Manual
Surface mount fuses, Ceramic fuse > 438 series
© 2013 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 12/19/13
Surface Mount Fuses
Ceramic Fuse > 438 Series
438 Series – 0603 Fast-Acting Fuse
Description
The 438 Series is a 100% Lead-free, RoHS compliant and
Halogen-free fuse series designed specifically to provide
over-current protection to circuits that operate under high
working ambient temperature up to 150ºC.
The general design ensures excellent temperature stability
and performance reliability.
The high I²t values which is typical in the Littelfuse Ceramic
Fuse family ensure high inrush current withstand capability.
Agency Approvals
AgeNCy
AgeNCy FIle NumbeR
AmpeRe RANge
e10480
0.250A – 6A
lR29862
0.250A – 6A
Features
Electrical Characteristics for Series
• Operating Temperature
from -55ºC to +150ºC
• 100% Lead-free, RoHS
compliant and Halogen-
free
• Suitable for both leaded
and lead-free reflow /
wave soldering
% of Ampere
Rating
Ampere Rating
Opening Time at 25ºC
100%
0.250A – 6A
4 Hours, Minimum
250%
0.250A – 6A
5 Seconds, Maximum
Applications
Ampere
Rating
(A)
Amp
Code
max.
Voltage
Rating (V)
Interrupting Rating
Nominal
Resistance
(Ohms)
2
Nominal
melting I
2
t
(A
2
Sec.)
3
Nominal Voltage
Drop At Rated
Current (V)
4
Nominal power
Dissipation At
Rated Current (W)
Agency Approvals
0.25
.250
63VDC
50A @ 63VDC
50A @ 32VAC
2.024
0.0017
0.550
0.138
x
x
0.375
.375
63VDC
1.247
0.0041
0.488
0.183
x
x
0.5
.500
63VDC
0.829
0.0100
0.486
0.243
x
x
0.75
.750
63VDC
0.466
0.0281
0.378
0.284
x
x
1
001.
63VDC
0.310
0.0593
0.351
0.351
x
x
1.25
1.25
63VDC
0.200
0.0510
0.365
0.456
x
x
1.5
01.5
63VDC
0.174
0.0902
0.368
0.552
x
x
1.75
1.75
63VDC
0.125
0.1440
0.360
0.540
x
x
2
002.
32
50A @ 32VDC/12VAC
0.051
0.1490
0.107
0.214
x
x
2.5
02.5
32
0.0324
0.1977
0.095
0.238
x
x
3
003.
32
0.0252
0.2922
0.093
0.279
x
x
3.5
03.5
32
0.0203
0.4752
0.082
0.287
x
x
4
004.
32
0.0169
0.6920
0.079
0.316
x
x
5
005.
32
0.0113
0.7398
0.074
0.370
x
x
6
006.
24
50A @ 24VDC/12VAC
0.0087
1.3838
0.072
0.432
x
x
Electrical Specifications by Item
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 msec. opening time.
4. Nominal Voltage Drop measured at rated current after temperature has stabilized.
• Handheld Electronics
• LCD Displays
• Battery Packs
• Hard Disk Drives
• SD Memory Cards
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.
Additional Information