Datasheet

© 2012 Littelfuse, Inc.
Specifications are subject to change without notice.
Axial Lead & Cartridge Fuses
251/253 Series
Please refer to www.littelfuse.com/series/251.html
or /253.html for current information.
PICO
®
ll > Very Fast-Acting > 251/253 Series
251/253 Series
Average Time Current Curves
Soldering Parameters
100
10
1
0.1
0.01
0.001
.062A
0.05 0.1 1 10 100 1000
.125A .250A .375A .500A .750A .630A 1A 1.5A 2A 2.5A 3A 3.5A 4A 5A 7A 10A 12A 15A
TIME IN SECONDS
CURRENT IN AMPERES
1.25A
Wave Parameter Lead-Free Recommendation
Preheat:
%FQFOETPO'MVY"DUJWBUJPO5FNQFSBUVSF
5ZQJDBM*OEVTUSZ3FDPNNFOEBUJPO
Temperature Minimum:
100
° C
Temperature Maximum:
150
° C
Preheat Time: 60-180 seconds
Solder Pot Temperature:
260
° C Maximum
Solder Dwell Time: 2-5 seconds
Recommended Hand Soldering Parameters:
4PMEFS*SPO5FNQFSBUVSF¡$¡$
Heating Time: 5 seconds max.
Note: These devices are not recommended for IR or
Convection Reflow process
Recommended Process Parameters:
Note:
1. Rerating depicted in this curve is in addition to the standard rerating of 25% for
continuous operation.
Temperature Rerating Curve