Surface Mount Fuses
Ceramic Fuse > 501 Series
501 Series – High Current 1206 Fast-Acting Fuse
Description
The 501 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 150°C.
The general design ensures excellent temperature stability
and performance reliability.
The high I
2
t values which is typical in the Littelfuse
Ceramic Fuse family, ensure high inrush current withstand
capability.
Agency Approvals
Agency
Agency File number
e10480
lr29862
Ampere rAnge
10A - 20A
10A - 20A
Features
• Operating Temperature
from -55ºC to +150ºC
• Designed to provide
over-current protection
in high current voltage
regulator module (VRM)
applications
Applications
• Voltage Regulator
Module (VRM)
Equipment
• Notebook PC
• DC-DC Converter
• 100% Lead-free, RoHS
compliant and Halogen-
free
• Suitable for both leaded
and lead-free reflow /
wave soldering
Electrical Characteristics for Series
% of Ampere
rating
100%
350%
Ampere rating
10A – 20A
10A – 20A
Opening Time at 25ºc
4 Hours, Minimum
5 Seconds, Maximum
Electrical Specifications by Item
Ampere
rating
(A)
10
12
15
20
Notes:
1. DC Interrupting Rating tested at rated voltage with time constant < 0.5 msec.
2. Nominal Resistance measured with < 10% rated current.
3. Nominal Melting I
2
t measured at 1 msec. opening time. For other I
2
t data refer to chart.
4. Nominal Voltage Drop measured at rated current after temperature has stabilized and
with fuse mounted on board with 3-oz Cu trace.
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.
Amp
code
010.
012.
015.
020.
max. Voltage
rating
(V)
32
32
32
32
interrupting
rating
(Dc)
1
nominal
nominal
resistance melting i
2
T
(Ohms)
2
(A
2
Sec.)
3
0.00427
10.385
20.341
36.100
54.760
0.00321
0.00250
0.00200
nominal Voltage
Drop At rated
current (V)
4
0.05679
0.04891
0.04605
0.05936
nominal power Agency Approvals
Dissipation At
rated current (W)
0.5679
0.5870
0.6908
1.1871
x
x
x
x
x
x
x
x
150 A @ 32 VDC
© 2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/501.html for current information.
25
Revised: June 23, 2011
501 Series
501 Series
Surface Mount Fuses
Introduction to Circuit Protection
Transientology
Ceramic Fuse > 501 Series
Temperature Rerating Curve
Average Time Current Curves
10A
12A
15A
20A
140
PERCENT OF RATING
120
10
100
80
TIME IN SECONDS
1
60
40
0.1
-65
-45
-25
-5
15
35
55
75
95
115
135
155
TEMPERATURE (°C)
0.01
Note:
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)I
RAT
= (0.68)I
RAT
0.001
1
10
100
1000
CURRENT IN AMPERES
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 – 180 seconds
3°C/second max.
5°C/second max.
217°C
60 – 150 seconds
260
+0/-5
°C
10 – 30 seconds
6°C/second max.
8 minutes max.
260°C
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
time to peak temperature
(t 25ºC to peak)
25
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
260°C, 10 seconds max.
501 Series
26
© 2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/501.html for current information.
Surface Mount Fuses
Ceramic Fuse > 501 Series
Product Characteristics
Body:
Advanced Ceramic
Terminations:
Ag / Ni / Sn (100% Lead-free)
Element Cover Coating:
Lead-free Glass
Moisture Resistance
Thermal Shock
Mechanical Shock
Vibration
Vibration,
High Frequency
Dissolution of
Metallization
Terminal Strength
MIL
-STD-202, Method 106G
MIL
-STD-202, Method 107G,
Condition B
MIL
-STD-202, Method 213B,
Condition A
MIL
-STD-202, Method 201A
MIL
-STD-202, Method 204D,
Condition D
IPC/ECA/JEDEC J-STD-002C,
Condition D
Materials
Moisture
IPC/JEDEC J-STD-020C, Level 1
Sensitivity Level
Solderability
Humidity Test
Resistance to
Solvents
IPC/ECA/JEDEC J-STD-002C, Condition B
MIL-STD-202, Method 103B, Conditions D
MIL-STD-202, Method 210F
, Condition B
Dimensions
3.200 ± .1778
[.126 ± .007]
Part Marking System
Amp code
010.
012.
015.
1.00
[.04]
1.63 +.10/-.20
[.064 +.004/-.008]
marking code
10
12
15
20
20
020.
0.835 ± 0.15
[.033 ± .006]
Part Numbering System
0501 020. W R T
Thin Version
.502 ± .08
[.02 ± .003]
Series
AMP Code
Quantity
W = 3000 pcs
TERMINATION
.520 ± .200
[.020 ± .008]
1.000
[.039]
1.500
[.059]
Packing Code
R = Reel Pack
Thickness Code
1.800
[.071]
T = Thin Version
3.500
[.138]
Packaging
packaging Option
8mm Tape and Reel
packaging Specification
EIA-481, IEC 60286, Part 3
Quantity
3000
Quantity &
packaging code
WR
© 2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/501.html for current information.
27
501 Series
501 Series
IEC 60127-4