POLYFUSE
®
Resettable PTCs
Radial Leaded > 250R Series
250R Series
Description
The 250R Series is designed to protect against short
duration high voltage fault currents (power cross or power
induction surge) typically found in telecom applications
(250Vrms). The series can be used to help telecom
networking equipment meet the protection requirements
specified in ITU
K.20
and
K.21.
Features
lead-free
Agency Approvals
AGENCY
AGENCY FILE NUMBER
E183209
R50120008
range, 60VDC operating
voltage
resistance ranges available
Applications
Equipment (CPE)
telecom centers
Part Number
I
hold
(A)
0.08
0.08
0.12
0.12
0.12
0.12
0.12
0.12
0.12
0.12
0.145
0.145
0.145
0.145
0.18
0.18
I
trip
(A)
0.16
0.16
0.24
0.24
0.24
0.24
0.24
0.24
0.24
0.24
0.29
0.29
0.29
0.29
0.65
0.65
V
max
V
int
/ V
op
250/60
250/60
250/60
250/60
250/60
250/60
250/60
250/60
250/60
250/60
250/60
250/60
250/60
250/60
250/60
250/60
I
max
(A)
3
3
3
3
3
3
3
3
3
3
3
3
3
3
10
10
P
d
max.
(W)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1.8
1.8
Maximum Time
To Trip
Current
(A)
0.35
0.35
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Time
(Sec.)
3
3
1.5
1.0
0.85
0.7
0.8
0.7
1
1.2
2.5
5
2.5
2.0
21
20
R
min
(Ω)
14
15
4
7
5.4
6
6
8
8
7
3
3
4.5
5.4
0.8
1.4
Resistance
R
typ
(Ω)
22
22
8
9
7
.5
10.5
9
10.5
10
12
6
5.5
6
7
.5
2.2
3.9
R
1max
(Ω)
33
33
16
16
14
16
16
16
16
16
14
12
14
14
4
4.5
Agency
Approvals
250R080
250R080T
250R120
250R120-RA
250R120-RC
250R120-RF
250R120-R1
250R120-R2
250R120-R3
250R120T
250R145
250R145-RA
250R145-RB
250R145T
250R180
250R180T
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Items with T at end of part number = pre-tripped device. See Part Ordering Number System section of this data sheet for additional information.
I
hold
= Hold current: maximum current device will pass without tripping in 23°C still air.
I
trip
= Trip current: minimum current at which the device will trip in 23°C still air.
V
int
= Maximum voltage the device can withstand without damage at rated current (I max)
V
op
= The device regular operation voltage
I
max
= Maximum fault current device can withstand without damage at rated voltage (V
max
)
P
d
= Power dissipated from device when in the tripped state at 23°C still air.
©2008 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/250R.html for current information.
R
min
= Minimum resistance of device in initial (un-soldered) state.
R
typ
= Typical resistance of device in initial (un-soldered) state.
R
1max
= Maximum resistance of device at 20°C measured one hour after tripping.
Caution:
Operation beyond the specified rating may result in damage and possible arcing
and flame.
Revised: October 24, 2008
250R Series
250R Series
Electrical Characteristics
POLYFUSE
®
Resettable PTCs
Radial Leaded > 250R Series
Temperature Rerating
Ambient Operation Temperature
-40°C
Part Number
250R080
250R080T
250R120
250R120T
250R145
250R145T
250R180
250R180T
0.12
0.12
0.18
0.18
0.26
0.26
0.28
0.28
0.11
0.11
0.16
0.16
0.20
0.20
0.23
0.23
0.09
0.09
0.14
0.14
0.17
0.17
0.21
0.21
0.08
0.08
0.12
0.12
0.145
0.145
0.18
0.18
-20°C
0°C
23°C
40°C
Hold Current (A)
0.06
0.06
0.10
0.10
0.12
0.12
0.16
0.16
0.05
0.05
0.09
0.09
0.11
0.11
0.13
0.13
0.05
0.05
0.08
0.08
0.09
0.09
0.10
0.10
0.04
0.04
0.06
0.06
0.08
0.08
0.11
0.11
0.03
0.03
0.05
0.05
0.06
0.06
0.083
0.083
50°C
60°C
70°C
85°C
Average Time Current Curves
0.080A
0.120A
0.145A
0.180A
Temperature Rerating Curve
170%
Percentage of Rated Current
100000
250R
150%
130%
110%
90%
70%
50%
30%
10%
-40 -30 -20
-10
0
10
10000
1000
Time in Seconds
100
10
20 30 40
Temperature (°C)
50
60
70
80
1
0.1
0.01
0.1
1
10
100
Current in Amperes
The average time current curves and Temperature Rerating curve performance is affected
by a number or variables, and these curves provided as guidance only. Customer must
verify the performance in their application.
250R Series
Revised: October 24, 2008
©2008 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/250R.html for current information.
POLYFUSE
®
Resettable PTCs
Radial Leaded > 250R Series
Agency Specification Selection Guide For Telecom and Networking Applications
Product
250R120
250R145
250R180
Lightning
ITU
K.20/21/45
– 1.5kV 10/700μs
ITU
K.20/21/45
– 4kV 10/700μs*
ITU
K.20/21/45
– 1.5kV 10/700μs
ITU
K.20/21/45
– 4kV 10/700μs*
Telcordia GR – 974 – 1.0kV 10/1000μs
Power Cross
ITU
K.20/21/45
– 230Vac, 10Ω
ITU
K.20/21/45
– 600Vac, 600Ω
ITU
K.20/21/45
– 230Vac, 10Ω
ITU
K.20/21/45
– 600Vac, 600Ω
Telcordia GR – 974- 283Vac, 10A
*Devices should be independently evaluated and tested for use in any specific application
Protection Application Guide
Region/Specification
Application
*Access network equipment
Remote terminal
Repeaters
WAN equipment
Cross –connect
Customer and IT equipment
Analog modems
ADSL, xDSL
Phone sets, PBX systems
Internet appliances
POS terminals
Central Office
POTS/ISDN linecards
T1/E1/J1 linecards
ADSL/VDSL splitters
CSU/DSU
Device Selection
250R180
250R180T
250R145
250R145T
250R120
250R120T
250R180
250R180T
250R145
250R145T
250R120
250R120T
250R180
250R180T
250R145
250R145T
250R120
250R120T
250R180
250R180T
250R145
250R145T
250R120
250R120T
250R180
250R180T
250R145
250R145T
250R120
250R120T
250R080
South America/Asia/Europe
ITU
K.45
South America/Asia/Europe
ITU
K.21
North America Telcordia
GR-974
South America/Asia/Europe
ITU
K.20
North America Telcordia
GR-1089
South America/Asia/Europe
ITU
K.20
and
K.21
*Primary protection modules
MDF modules
Network interface
*Intrabuilding communication systems
LAN, VOIP cards
Local loop handsets
LAN Intrabuilding power cross
Protection
LAN equipment, IP phone
*Resistance binned parts are recommended
©2008 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/250R.html for current information.
Revised: October 24, 2008
250R Series
250R Series
South America/Asia/Europe
ITU
K.20
POLYFUSE
®
Resettable PTCs
Radial Leaded > 250R Series
Soldering Parameters - Wave Soldering
Condition
Peak Temp/ Duration Time
>
220°C
Preheat 140°C ~ 180°C
Storage Condition
Wave Soldering
260°C < 5 Sec
2 Sec ~ 20 Sec
Temperature (°C)
260
220
Soldering
Cooling
180 Sec ~ 210 Sec
0°C~35°C < 70%RH
Preheating
190
160
N
2
environment for lead-free.
side of the board.
0
and solvents.
Note:
If soldering temperatures exceed the recommended
profile, devices may not meet the performance
requirements.
Soldering Parameters - Solder Reflow
Condition
Peak Temp/ Duration Time
>
220°C
Preheat 160°C ~ 190°C
Storage Condition
Reflow
260°C > 5 Sec
30 Sec ~ 60 Sec
Temperature (°C)
260
220
180 to 210
2 to 5
Time(s)
20-30
Soldering
Cooling
60 Sec ~ 90 Sec
0°C~35°C, < 70%RH
Preheating
190
160
air oven, N
2
environment for lead-free.
bottom side of the board.
0
and solvents.
Note:
If reflow temperatures exceed the recommended
profile, devices may not meet the performance
requirements.
Physical Specifications
60 to 90
30 to 60
Time(s)
120
Environmental Specifications
Operating/Storage
Temperature
Maximum Device Surface
Temperature in Tripped State
Passive Aging
Humidity Aging
-40°C to +85°C
125°C
65°C/85°C, 1000 hours
+85°C, 85% R.H,.1000 hours
MIL–STD–202F Method 107G
,
+125°C to -55°C 10 times
MIL–STD–202, Method 215F
Level 2, J–STD–020C
Lead Material
Soldering
Characteristics
Insulating Material
Device Labeling
Tin-plated Copper
Solderability per MIL–STD–202,
Method 208E
Cured, flame retardant epoxy polymer
meets UL94V-0 requirements.
Marked with 'LF', voltage, current rating,
and date code.
Thermal Shock
Solvent Resistance
Moisture Sesitivity Level
250R Series
Revised: October 24, 2008
©2008 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/250R.html for current information.
POLYFUSE
®
Resettable PTCs
Radial Leaded > 250R Series
Dimensions
A
C
A
C
Part Marking System
Littelfuse
Trademark
080
XXXX
250
B
B
Littelfuse
Voltage Rating
Trademark
Current Rating
Date Code
(Contact Littelfuse
for additional
information)
120
XXXX
250
Voltage Rating
Current Rating
Date Code
(Contact Littelfuse
for additional
information)
D
D
E
F
E
F
Figure 1
A
Part Number
250R080
250R080T
250R120
250R120-RA
250R120-RC
250R120-RF
250R120-R1
250R120-R2
250R120-R3
250R120T
250R145
250R145-RA
250R145-RB
250R145T
250R180
250R180T
Figure
1
1
2
2
2
2
2
2
2
2
2
2
2
2
1
1
Inches
Max.
0.23
0.23
0.26
0.26
0.26
0.26
0.26
0.26
0.26
0.26
0.26
0.26
0.26
0.26
0.37
0.37
mm
Max.
5.8
5.8
6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.5
9.5
9.5
Figure 2
B
Inches
Max.
0.39
0.39
0.43
0.43
0.43
0.43
0.43
0.43
0.43
0.43
0.43
0.43
0.43
0.43
0.47
0.47
mm
Max.
9.9
9.9
11
11
11
11
11
11
11
11
11
11
11
11
12
12
Max.
0.18
0.18
0.15
0.18
0.18
0.18
0.18
0.18
0.18
0.18
0.18
0.18
0.18
0.18
0.18
0.18
C
Inches
mm
Max.
4.6
4.6
3.8
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
Min.
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
D
Inches
mm
Min.
4.7
4.7
4.7
4.7
4.7
4.7
4.7
4.7
4.7
4.7
4.7
4.7
4.7
4.7
4.7
4.7
Typ.
0.20
0.20
0.20
0.20
0.20
0.20
0.20
0.20
0.20
0.20
0.20
0.20
0.20
0.20
0.20
0.20
E
Inches
mm
Typ.
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
Physical Characteristics
Lead (dia)
Inches
0.026
0.026
0.026
0.026
0.026
0.026
0.026
0.026
0.026
0.026
0.026
0.026
0.026
0.026
0.026
0.026
mm
0.65
0.65
0.65
0.65
0.65
0.65
0.65
0.65
0.65
0.65
0.65
0.65
0.65
0.65
0.65
0.65
Material
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
Sn/Cu
©2008 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/250R.html for current information.
Revised: October 24, 2008
250R Series
250R Series
NXP MCU
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
