Surface Mount Fuses
NANO
2®
> Very Fast-Acting > 451/453 Series
Temperature Rerating Curve
Average Time Current Curves
.062A
.125A
.160A
.200A
.250A
.315A
.375A
.500A
.750A
1A
1.5A
2A
2.5A
3A
3.5A
4A
5A
7A
8A
10A
12A
15A
100
10
TIME IN SECONDS
0.1
0.01
Note:
1. Derating depicted in this curve is in addition to the standard derating of 25% for
continuous operation.
0.001
0.05 0.1
1
10
100
CURRENT IN AMPERES
1000
Soldering Parameters
Reflow Condition
- Temperature Min (T
s(min)
)
Pre Heat
- Temperature Max (T
s(max)
)
- Time (Min to Max) (t
s
)
Average ramp up rate (Liquidus Temp
(T
L
) to peak
T
S(max)
to T
L
- Ramp-up Rate
Reflow
- Temperature (T
L
) (Liquidus)
- Temperature (t
L
)
Pb – Free assembly
150°C
60 – 120 secs
5°C/second max.
5°C/second max.
217°C
60 – 90 seconds
250
+0/-5
T
P
T
L
Temperature
t
P
Ramp-up
Critical Zone
T
L
to T
P
200°C
T
S(max)
T
S(min)
Preheat
t
L
Ramp-down
t
S
25
time to peak temperature
(t 25ºC to peak)
Time
Peak Temperature (T
P
)
Time within 5°C of actual peak
Temperature (t
p
)
Ramp-down Rate
Time 25°C to peak Temperature (T
P
)
Do not exceed
Wave Soldering Parameters
°C
20 – 40 seconds
5°C/second max.
8 minutes max.
260°C
260°C Peak
Temperature,
10 seconds max.
© 2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/451.html
or /453.html for current information.
59
451/453 Series
451/453 Series
1
LITTELFUSE [ LITTELFUSE ]
