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Cross Reference
Littelfuse
Raychem
®
Bourns
®
Polytronics
1206L020
Not Available
1206L025
Not Available
1206L035
Not Available
SMD1206P035TS
1206L050
nanoSMDM050
SMD1206P050TS
1206L075
nanoSMDM075
SMD1206P075TS
1206L110
nanoSMDM110
SMD1206P110TS
1206L150
nanoSMDC150
SMD1206P150TS
1812L050
miniSMDC050
MF-MSMD050
SMD1812P050TS
1812L075
miniSMDC075
MF-MSMD075
SMD1812P075TS
1812L110
miniSMDC110
MF-MSMD110
SMD1812P110TS
1812L150
miniSMDC150
MF-MSMD150
SMD1812P150TS
1812L160
miniSMDM160
MF-MSMD160
SMD1812P160TS
1812L200
miniSMDC200
MF-MSMD200
SMD1812P200TS
1812L260
miniSMDC260
MF-MSMD260
SMD1812P260TS
3425L150
SMD150
MF-SM150
3425L200
SMD200
MF-SM200
3425L250
SMD250
MF-SM-250
3425L300
SMD300
MF-SM-300
30R090
RUE090
MF-R090-0-9
RLD30P090U
30R110
RUE110
MF-R110
RLD30P110U
30R135
RUE135
MF-R135
RLD30P135U
30R160
RUE160
MF-R160
RLD30P160U
30R185
RUE185
MF-R185
RLD30P185U
30R250
RUE250
MF-R250
RLD30P250U
30R300
RUE300
MF-R300
RLD30P300U
30R400
RUE400
MF-R400
RLD30P400U
30R500
RUE500
MF-R500
RLD30P500U
30R600
RUE600
MF-R600
RLD30P600U
30R700
RUE700
MF-R700
RLD30P700U
30R800
RUE800
MF-R800
RLD30P800U
30R900
RUE900
MF-R900
RLD30P900U
60R010
RXE010
MF-R010
RLD60P010X
60R017
RXE017
MF-R017
RLD60P017X
60R020
RXE020
MF-R020
RLD60P020X
60R025
RXE025
MF-R025
RLD60P025X
60R030
RXE030
MF-R030
RLD60P030X
60R040
RXE040
MF-R040
RLD60P040X
60R050
RXE050
MF-R050
RLD60P050X
60R065
RXE065
MF-R065
RLD60P065X
60R075
RXE075
MF-R075
RLD60P075X
60R090
RXE090
MF-R090
RLD60P090X
60R110
RXE110
MF-R110
RLD60P110X
60R135
RXE135
MF-R135
RLD60P135X
60R160
RXE160
MF-R160
RLD60P160X
60R185
RXE185
MF-R185
RLD60P185X
60R250
RXE250
MF-R250
RLD60P250X
60R300
RXE300
MF-R300
RLD60P300X
60R375
RXE375
MF-R375
RLD60P375X
Littelfuse
Raychem
®
Bourns
®
Polytronics
Cross Reference
I
Hold
(A)
= Hold Current - The maximum current the device will sustain for
4 hours without tripping in 20oC still air.
I
Trip
(A)
= Trip Current -The minimum current at which the device will trip in 20oC still air.
V
Max
(V
DC
)
= Maximum Voltage - The maximum voltage the device can withstand without damage at
rated current (I
Max
).
I
Max
(A)
= Maximum Fault Current - The maximum fault current the device can withstand without
damage at rated voltage (V
Max
).
P
d
Max (W)
= Power Dissipated from the device when in the tripped state in 20oC still air.
R
IL
( )
= The minimum resistance of the device in an initial (un-soldered) state.
R
AT
( )
= The maximum measured resistance in the non-tripped state one hour after reflow with
reflow conditions of 260oC for 20 seconds.
Electronic Definitions
800 E. Northwest Highway
Des Plaines, IL 60016
(847)824-1188
For local contact information go to:
www.littelfuse.com
Copyright © 2001 Littelfuse,Inc. Specifications, descriptions and illustrative
material in this literature are as accurate as known at the time of publication but
are subject to change without notice.
EC327D 3425L Series
PTCs are components that utilize a unique
polymer-based positive temperature coefficient
material that protects electrical equipment from
over-current conditions. Numerous carbon paths
within the polymer allow the device to conduct
electricity. As current through the device reaches
its rated threshold, the polymer material begins to
heat causing the polymer to expand. The resulting
expansion breaks the carbon chains to reduce
the current through the circuit to a small leakage
current. When the fault is removed from the
circuit, the device will reset itself thereby allowing
current to flow through the circuit again.
Where are they used?
PTCs are used as circuit protection in applications
where sensitive components are at risk of damage
from overcurrent conditions. The ability of PTCs
to reset themselves after exposure to a fault
current makes them ideal for use in circuits that are
not easily accessible to a user or technician. Typical
applications include port protection on personal
computers (USB, Firewire, keyboard/mouse, serial
ports), peripherals (hard drives, video cards, hubs),
cell phone, battery packs, industrial controls, lighting
ballast and motor controls.
USB PORT PROTECTION
USB is one of the most commonPlug and Play
interfaces. Designed as a hot-plug device, USB
ports are susceptible to overcurrent conditions
caused by potential differences and temporary
short circuits. An 1812L or 1206L series PTC
should be placed across the bus voltage of a USB
port to protect against over-current conditions
on the line. This allows the user to use plug &
play devices without having to service the
computer every time a fault condition occurs.
INDUSTRIAL CONTROLS
Industrial Controls typically use higher voltages
than computer applications. Littelfuse offers the
30R and 60R series of radial-leaded PTCs for use
in these higher voltage applications. The figure
below illustrates overcurrent protection on a typi-
cal transformer. Overcurrent conditions typically
result from a substantial decrease in the circuit
load or a short on the transformer output.
Typically this will result in arcing, burnt wiring or
fire unless over-current protection in used.
I
Hold
I
Trip
V
Max
I
Max
P
d
Max
Current
Time
R
IL
R
AT
Part Number
(A)
(A)
(V
DC
)
(A)
(W)
(A)
(Sec)
( )
( )
1812L050
0.50
1.00
15.0
40
0.8
8.0
0.15
0.100
1.000
1812L075
0.75
1.50
13.2
40
0.8
8.0
0.30
0.075
0.420
1812L110
1.10
2.20
6.0
40
0.8
8.0
0.30
0.040
0.226
1812L125
1.25
2.50
6.0
40
0.8
8.0
0.30
0.045
0.184
1812L150
1.50
3.00
6.0
40
0.8
8.0
0.30
0.030
0.099
1812L160
1.60
3.20
6.0
40
0.8
8.0
0.30
0.040
0.137
1812L200
2.00
4.00
6.0
40
0.8
8.0
2.50
0.018
0.070
1812L260
2.60
5.20
6.0
40
0.8
8.0
2.50
0.010
0.050
Maximum Time to Trip
Marking
I
Hold
I
Trip
V
Max
I
Max
P
d
Max
Current
Time
R
IL
R
AT
Part Number
Code
(A)
(A)
(V
DC
)
(A)
(W)
(A)
(Sec)
( )
( )
1206L020
C
0.20
0.40
15.0
40
0.8
8.0
0.05
0.600
2.500
1206L025
D
0.25
0.50
15.0
40
0.8
8.0
0.08
0.550
2.300
1206L035
E
0.35
0.70
6.0
40
0.8
8.0
0.10
0.250
0.800
1206L050 F
0.50
1.00
6.0
40
0.8 8.0
0.10
0.090
0.600

1206L075 G
0.75
1.50
6.0
40
0.8 8.0
0.20
0.070
0.300

1206L110 H
1.10
2.20
6.0
40
0.8 8.0
0.30
0.040
0.180
1206L150 K
1.50
3.00
6.0
40
0.8 8.0
0.30
0.030
0.120
Maximum Time to Trip
1206L Series
1812L Series
I
Hold
I
Trip
V
Max
I
Max
P
d
max
Current
Time
R
IL
R
AT
Part Number
(A)
(A)
(V
DC
)
(A)
(W)
(A)
(Sec)
( )
( )
3425L150
1.50
3.00
15.0
40
1.9
8.0
5.00
0.060
0.250
3425L200
2.00
4.00
15.0
40
1.9
8.0
12.0
0.050
0.150
3425L250
2.50
5.00
15.0
40
1.9
8.0
25.0
0.035
0.100
3425L300
3.00
6.00
6.0
40
1.9
8.0
32.0
0.020
0.060
Maximum Time to Trip
I
Hold
I
Trip
V
Max
I
Max
P
d
Max
Current
Time
R
IL
R
AT
Part Number
(A)
(A)
(V
DC
)
(A)
(W)
(A)
(Sec)
( )
( )
30R090
0.90
1.80
30.0
40
0.6
4.5
5.90
0.07
0.22
30R110
1.1
2.2
30.0
40
0.7
5.5
6.6
0.05
0.17
30R135
1.35
2.7
30.0
40
0.8
6.75
7.3
0.04
0.13
30R160
1.6
3.2
30.0
40
0.9
8
8
0.03
0.11
30R185
1.85
3.7
30.0
40
1
9.25
8.7
0.03
0.09
30R250
2.5
5
30.0
40
1.2
12.5
10.3
0.02
0.07
30R300
3
6
30.0
40
2
15
10.8
0.02
0.08
30R400
4
8
30.0
40
2.5
20
12.7
0.01
0.05
30R500
5
10
30.0
40
3
25
14.5
0.01
0.05
30R600
6
12
30.0
40
3.5
30
16
0.005
0.04
30R700
7
14
30.0
40
3.8
35
17.5
0.005
0.03
30R800
8
16
30.0
40
4
40
18.8
0.005
0.02
30R900
9
18
30.0
40
4.2
45
20
0.005
0.02
Maximum Time to Trip
30R Radial Leaded
OUTSIDE W
ORLD
I
Hold
I
Trip
V
Max
I
Max
P
d
Max
Current
Time
R
IL
R
AT
Part Number
(A)
(A)
(V
DC
)
(A)
(W)
(A)
(Sec)
( )
( )
60R010
0.10
0.20
60
40
0.38
0.50
4.0
2.5
7.5
60R017
0.17
0.34
60
40
0.48
0.85
3.0
3.3
8
60R020
0.20
0.40
60
40
0.41
1.00
2.2
1.83
4.4
60R025
0.25
0.50
60
40
0.45
1.25
2.5
1.25
3
60R030
0.30
0.60
60
40
0.49
1.50
3.0
0.88
2.1
60R040
0.40
0.80
60
40
0.56
2.00
3.8
0.55
1.29
60R050
0.50
1.00
60
40
0.77
2.50
4.0
0.5
1.17
60R065
0.65
1.30
60
40
0.88
3.25
5.3
0.31
0.72
60R075
0.75
1.50
60
40
0.92
3.75
6.3
0.25
0.6
60R090
0.90
1.80
60
40
0.99
4.50
7.2
0.2
0.47
60R110
1.10
2.20
60
40
1.50
5.50
8.2
0.15
0.38
60R135
1.35
2.17
60
40
1.70
6.75
9.6
0.12
0.3
60R160
1.60
3.20
60
40
1.90
8.00
11.4
0.09
0.22
60R185
1.85
3.70
60
40
2.10
9.25
12.6
0.08
0.19
60R250
2.50
5.00
60
40
2.50
12.50
15.6
0.04
0.13
60R300
3.00
6.00
60
40
2.80
15.00
19.8
0.03
0.1
60R375
3.75
7.50
60
40
3.20
18.75
24.0
0.02
0.08
Maximum Time to Trip
60R Radial Leaded
PTC 3425L Series
PTCs are components that utilize a unique
polymer-based positive temperature coefficient
material that protects electrical equipment from
over-current conditions