Selector Chart For Fuses
Resettable
Polymeric PTC
9E
NEW
ISO 9001 / ISO 14001
Fuses cross to competitive resettable devices. See our online cross list at http://www.schurterinc.com/cross.htm
Series
Page
Mounting terminals
Hold current I
H
@ 23˚C
PFMD
106 -108
surface mount
200mA to 1.1A
PFSM
109 - 111
surface mount
300mA to 2.5A
PFRA
112 -115
radial leaded
100mA to 9A
PFRX
116 -118
radial leaded
1.1A to 3.75A
PFST/PFLT
119 - 122
strap (standard or slotted)
1A to 4.2A
Non-
Resettable
Surface Mount
NEW
EIA 1206
With or without
fuse clips
NEW
Time-lag
version OMT
New MSB / MKT
Time lag versions
Series / Voltage
Page
Rated current
Time/current action
MGA 125V
127
200mA to 5A
quick-acting
SFP 63V; SFC 63V
128-129
1A-5A; 800mA-4A
quick-acting
OMF 63V
130-131
63mA to 10A
quick-acting
OMF 125
132-133
63mA to 10A
quick-acting
OMF/OMT 125/250V
134
250mA to 4A
MELF/MKF 125V
135-136
125mA to 7A
quick-acting or time-lag quick-acting or time-lag
UL listed versions
MSF-U & MST-U
Through-Hole
NEW
NEW
NEW
With radial leads
Hermetically
sealed
MXT with high
breaking capacity
Series / Voltage
Page
Rated current
Time/current action
MSA 125V
137
63mA to 15A
quick-acting
MGL 125V
138
200mA to 5A
quick-acting
MSF 125V
139
100mA to 5A
quick-acting
MSF 250V
140
40mA to 5A
quick-acting
MST/MXT 250V
141/142
50mA to 6.3A
time-lag
FRT 250V
143
250mA to 6.3A
quick-acting or time-lag
5 x 20mm
Series
Page
Quick-acting and time-lag characteristics available, with low, medium or high breaking capacities. Pigtail leads optional.
SA/SP/SPT/FSM
FSF/FST/FTT/FSM
All series
Fuse kits for prototypes
144 -154
144 - 154
144 - 154
156
Telecom
Surge-Tolerant for
Telecom applications
Series / Voltage
Page
Rated current
Time/current action
OSU 125V
162
250mA to 3.15A
quick-acting
OSU / OMT 250V
162
250mA to 3.15A
quick-acting
MSU 125V
163
250mA to 3.15A
quick-acting
MSU 250V
163
250mA to 3.15A
quick-acting
FRT 250V
164
250mA to 3.15A
quick-acting
FSU / SSU 250V
165-166
250mA to 3.15A
quick-acting
102
Schurter, Inc. • Phone 707-778-6311 • Fax 707-778-6401 • E-mail info@schurterinc.com • Website http://www.schurterinc.com
H O W P O LY M E R I C R E S E T TA B L E
O V E R C U R R E N T P R O T E C TO R S W O R K
The conductive carbon black filler material in the
polymeric device is dispersed in a polymer that has a
crystalline structure. The crystalline structure densely
packs the carbon particles into its crystalline
boundary so they are close enough
together to allow current to flow
through the polymer insulator
via these carbon Òchains.Ó
When the conductive
plastic material is
at normal room
temperature, there
are numerous carbon
chains forming conductive
paths through the material.
Under fault conditions, excessive current flows through
the polymeric device. I
2
R heating causes the conductive
plastic materialÕs temperature to rise. As this self heating
continues, the materialÕs temperature continues to
rise until it exceeds its phase transformation
temperature. As the material passes through this
phase transformation temperature, the densely packed
crystalline polymer matrix changes to an
amorphous structure. This phase change is
accompanied by a small expansion. As the
conductive particles move apart from each other, most of
them no longer conduct current and the resistance of the
device increases sharply.
The material will stay Òhot,Ó remaining in this high
resistance state as long as the power is applied. The
device will remain latched, providing continuous
protection, until the fault is cleared and the power is
removed. Reversing the phase transformation allows the
carbon chains to re-form as the polymer re-crystallizes.
The resistance quickly returns to its original value.
ST 3
50
RA
090
RA
075
RA
060
RA
600
RA
400
RA
300
R E S E T TA B L E C I R C U I T P R O T E C T I O N
When it comes to Polymeric Positive Temperature
Coefficient (PPTC) circuit protection, you now have a
choice. If you need a reliable source, look to polymeric
resettable fuses from SCHURTER.
Polymeric fuses are made from a conductive plastic
formed into thin sheets, with electrodes attached to either
side. The conductive plastic is manufactured from a non-
conductive crystalline polymer and a highly conductive
carbon black. The electrodes ensure even distribution of
power through the device, and provide a surface for leads
to be attached or for custom mounting.
The phenomenon that allows conductive plastic materials
to be used for resettable overcurrent protection devices is
that they exhibit a very large non-linear Positive
Temperature Coefficient (PTC) effect when heated. PTC
is a characteristic that many materials exhibit whereby
resistance increases with temperature. What makes the
polymeric conductive plastic material unique is the
magnitude of its resistance increase. At a specific
transition temperature, the increase in resistance is so
great that it is typically expressed on a log scale.
10
7
10
6
10
5
LOG R OHMS
10
4
10
3
10
2
10
1
10
0
0
20
40
60
80
TEMPERATURE
°C
100
120
140
104
Schurter, Inc. ¥ Phone 707-778-6311 ¥ Fax 707-778-6401 ¥ E-mail info@schurter.com ¥ Website http://www.schurter.com
PRODUCT SELECTION
To select the correct polymeric circuit
protection device, complete the information listed below
for the application, and then refer to the resettable
overcurrent protector data sheets.
A P P L I C AT I O N S
The benefits of polymeric Resettable Overcurrent
Protectors are being recognized by more and more
design engineers, and new applications are being
discovered every day.
The use of polymeric types of devices have been widely
accepted in the following applications and industries:
1. Determine the normal operating current:
______ amps
2. Determine the maximum circuit voltage
(Vmax): ______ volts
3. Determine the fault current (Imax):
______ amps
4. Determine the operating temperature range:
Minimum Temperature: ______ ¡C
Maximum Temperature: ______ ¡C
5. Select a product family so that the maximum
rating for Vmax and Imax is higher than the maximum
circuit voltage and fault current in the application.
6. Using the Ihold vs. Temperature Table on the product
family data sheet, select the polymeric device at the
maximum operating temperature with an Ihold greater
than or equal to the normal operating current.
7. Verify that the selected device will trip under fault
conditions by checking in the Itrip table that the fault
current is greater than Itrip for the selected device, at
the lowest operating temperature.
8. Order samples and test in application.
¥ Personal computers
¥ Laptop computers
¥ Personal digital assistants
¥ Transformers
¥ Small and medium electric motors
¥ Audio equipment and speakers
¥ Test and measurement equipment
¥ Security and fire alarm systems
¥ Medical electronics
¥ Personal care products
¥ Point-of-sale equipment
¥ Industrial controls
¥ Automotive electronics and harness protection
¥ Marine electronics
¥ Battery-operated toys
SchurterÕs resettable fuses cross to many like products already on the
market.
See our online cross list at www.schurterinc.com/cross.htm.
105
Schurter, Inc. ¥ Phone 707-778-6311 ¥ Fax 707-778-6401 ¥ E-mail info@schurter.com ¥ Website http://www.schurter.com
PFMD
Polymeric PTC Resettable Fuse – Surface Mount
Typical Time to Trip at 23 °C
PF
MD
.02
0
PF
MD
.03
5
PF
MD
.05
0
PF
MD
PF
.075
MD
.11
0
NEW
•
High Density Circuit Board Application:
100
Time to Trip (Seconds)
Hard disk drives,
PC motherboards
PC peripherals
Point-of-sale (POS) equipment
PCMCIA cards
•
Packaged per EIA 481-2 standard
10
9E
1
0.1
Approvals:
UL
CSA
TÜV
recognition
pending
approval
0.01
0.001
0.1
1
10
100
Fault current (Amps)
Dimensions
A
C
Solder Pad Layouts
1.00
(0.039)
2.5
(0.098)
2.00
(0.079)
PFMD.035
3.45
(0.136)
PFMD.020, 050, 075, 110
1.78
(0.070)
3.15
(0.124)
Typical Part Marking
Represents total content. Layout may vary.
PART
IDENTIFICATION
B
MANUFACTURER'S
TRADEMARK
110
9E
MIN
D
TOP
VIEW
SIDE
VIEW
MIN
Dimentions in mm / (inch)
Technical Data
Operating/Storage Temperature
Maximum Device Surface Temperature
in Tripped State
Passive Aging
Humidity Aging
Thermal Shock
Mechanical Shock
Solvent Resistance
Vibration
Terminal material
Termination pad solderability
-40°C to +85°C
125°C
+85°C, 1000 hours
±5% typical resistance change
+85°C, 85% R.H. 1000 hours
±5% typical resistance change
+125°C/-40°C 10 times
±10% typical resistance change
MIL-STD-202, Method 213,
No resistance change
Condition 1 (100g, 6 seconds)
MIL-STD-202, Method 215
No change
MIL-STD-883C, Method 2007.1,
No change
Condition A
Solder-plated copper
Meets EIA Specification RS-186-9E, ANSI/J-STD-002 Cat.3
Test Procedures And Requirements
Test Conditions
Accept/Reject Criteria
Verify dimensions and materials
In still air @ 23°C
At 8 Amps , Vmax, 23°C
30 min. at Ihold
Vmax, Imax, 100 cycles
Vmax, 48 hours
Per PF physical description
Rmin
≤
R
≤
Rmax
T
≤
max. time to trip (seconds)
No trip
No arcing or burning
No arcing or burning
Test
Visual/Mech.
Resistance
Time to Trip
Hold Current
Trip Cycle Life
Trip Endurance
106
Schurter, Inc. • Phone 707-778-6311 • Fax 707-778-6401 • E-mail info@schurterinc.com • Website http://www.schurterinc.com
PFMD
Technical Data, continued
Electrical Characteristics
Ihold
Model
I max.
Amps
V max.
Volts
Itrip
Initial
Resistance
Ohms
at 23°C
R Min.
R1Max.
Max. Time
To Trip at 23°C
Amps
Seconds
Tripped
Power
Dissipation
Amperes
at 23°C
Hold
Trip
Watts
at 23°C
PFMD.020.2
PFMD.035.2
PFMD.050.2
PFMD.075.2
PFMD.110.2
10
40
40
40
40
30.0
6.0
15.0
13.2
6.0
0.20
0.35
0.50
0.75
1.10
0.40
0.70
1.00
1.50
2.20
0.40
0.32
0.15
0.11
0.04
5.00
1.30
1.00
0.45
0.21
8.0
8.0
8.0
8.0
8.0
0.02
0.10
0.15
0.20
0.30
0.8
0.6
0.8
0.8
0.8
Product Dimensions
Model
PFMD.020.2
PFMD.035.2
PFMD.050.2
PFMD.075.2
PFMD.110.2
A
Min.
4.37
3.00
4.37
4.37
4.37
Max.
4.73
3.43
4.73
4.73
4.73
Min.
3.07
2.35
3.07
3.07
3.07
B
Max.
3.41
2.80
3.41
3.41
3.41
Min.
0.56
0.38
0.38
0.38
0.38
C
Max.
0.81
0.62
0.62
0.62
0.62
D
Min.
0.30
0.35
0.30
0.30
0.30
How to Order
PFMD.020.2
Product Designator
Solder Reflow And Rework Recommendations
Preheating
300
Soldering
Cooling
Style
MD = 4.5mm SMD
Hold Current, Ihold
020-110 (0.20 Amps - 1.10 Amps)
Packaging
.2 = 1,500 pcs. tape & reel
Temperature (˚C)
250
200
150
100
50
•
Packaging options:
•
TAPE & REEL: PFMD.035.2 = 3000 pcs per reel
All other models = 1500 pcs. per reel.
NOTE:
• PFMD models can be waved soldered and reworked.
• If reflow temeratures exceed the recommended profile, devices may not
meet the performance requirements.
30–90
sec
10–20
sec
120
sec
Thermal Derating Chart - Ihold (Amps)*
Ambient Operating Temperature
Part
No.
PFMD.020.2
PFMD.035.2
PFMD.050.2
PFMD.075.2
PFMD.110.2
-40˚C
0.29 / 0.58
0.47 / 0.94
0.77 / 1.54
1.15 / 2.30
1.59 / 3.18
-20˚C
0.26 / 0.52
0.45 / 0.90
0.68 / 1.36
1.01 / 2.02
1.43 / 2.86
0˚C
0.23 / 0.46
0.40 / 0.80
0.59 / 1.18
0.88 / 1.76
1.26 / 2.52
23˚C
0.20 / 0.40
0.35 / 0.70
0.50 / 1.00
0.75 / 1.50
1.10 / 2.20
40˚C
0.17 / 0.34
0.30 / 0.60
0.44 / 0.88
0.65 / 1.30
0.95 / 1.90
50˚C
0.15 / 0.30
0.28 / 0.56
0.40 / 0.80
0.60 / 1.20
0.87 / 1.74
60˚C
0.14 / 0.28
0.24 / 0.48
0.37 / 0.74
0.55 / 1.10
0.80 / 1.60
70˚C
0.12 / 0.24
0.21 / 0.42
0.33 / 0.66
0.49 / 0.98
0.71 / 1.42
85˚C
0.10 / 0.20
0.18 / 0.36
0.29 / 0.58
0.43 / 0.86
0.60 / 1.20
*Itrip = 2 • Ihold
Schurter’s resettable fuses cross to many like products already on the market. See our online cross list at www.schurterinc.com/cross.htm
Schurter, Inc. • Phone 707-778-6311 • Fax 707- 778-6401 • E-mail info@schurterinc.com • Website http://www.schurterinc.com
107
