MF-USML/X Series - Low Ohmic PTC Resettable Fuses
* RoHS Directive 2015/863, Mar 31, 2015 and Annex.
** Bourns considers a product to be “halogen free” if (a) the Bromine (Br) content is 900 ppm or less; (b) the Chlorine (Cl) content is 900 ppm or less; and (c) the total Bromine (Br)
and Chlorine (Cl) content is 1500 ppm or less.
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
Electrical Characteristics
Model V max. I max.
Ihold Itrip Resistance Max. Time To Trip Tripped
Power
Dissipation Certications
at 23 °C at 23 °C Ohms at 23 °C Watts at
23 °C cUL TÜV
Volts Amps Amps Rmin R1max Amps Seconds Typ. E174545 R50391579
MF-USML175/12 12 50 1.75 3.5 0.006 0.050 8.0 0.8 1.0 3 3
MF-USML200/12 12 50 2.0 4.0 0.005 0.040 8.0 5.0 1.0 3 3
MF-USML260/12 12 50 2.6 5.2 0.004 0.030 8.0 5.0 1.0 3 3
MF-USML300/12 12 50 3.0 6.0 0.003 0.024 15.0 5.0 1.0 3 3
MF-USML350/12 12 50 3.5 7.0 0.002 0.022 17.0 5.0 1.0 3 3
MF-USML380/12 12 50 3.8 7.6 0.002 0.020 19.0 5.0 1.0 3 3
MF-USML400/12 12 50 4.0 8.0 0.002 0.018 20.0 5.0 1.0 3 3
MF-USML450/12 12 50 4.5 9.0 0.002 0.014 22.5 2.0 1.0 3 3
MF-USML500/12 12 50 5.0 10.0 0.001 0.012 25.0 2.0 1.2 3 3
MF-USML550/12 12 50 5.5 11.0 0.001 0.010 27.5 2.0 1.2 3 3
Environmental Characteristics
Operating Temperature ......................................... -40 °C to +85 °C
Storage Condition
Before Opening ............................................... +40 °C max. / 70 % RH max.
After Opening................................................... +40 °C max. / 10 % RH max.
Floor Condition After Opening .............................. Consumption within 4 weeks at oor condition +30 °C max. / 60 % RH max.
Passive Aging ....................................................... +85 °C, 1000 hours ............................................... ±10 % typical resistance change
Humidity Aging...................................................... +85 °C, 85 % R.H. 100 hours ............................... ±15 % typical resistance change
Thermal Shock ..................................................... +85 °C to -40 °C, 20 times .................................... ±30 % typical resistance change
Solvent Resistance ............................................... MIL-STD-202, Method 215 ................................... No change (marking still legible)
Vibration ............................................................... MIL-STD-883C, Method 2007.1, ........................... No change (Rmin<R<R1max)
Condition A
Moisture Sensitivity Level (MSL) .......................... See Note
ESD Classication - HBM ..................................... 6
Test Procedures and Requirements
Test Test Conditions Accept/Reject Criteria
Visual/Mech. ......................................................... Verify dimensions and materials ........................... Per MF physical description
Resistance ............................................................ In still air @ 23 °C ................................................. Rmin ≤ R ≤ R1max
Time to Trip ........................................................... At specied current, Vmax, 23 °C .......................... T ≤ max. time to trip (seconds)
Hold Current ......................................................... 30 min. at Ihold ...................................................... No trip
Trip Cycle Life ....................................................... Vmax, Imax, 100 cycles.......................................... No arcing or burning
Trip Endurance ..................................................... Vmax, 48 hours ..................................................... No arcing or burning
Solderability .......................................................... 245 °C ±5 °C, 5 seconds ...................................... 95 % min. coverage
Features
n Surface mount packaging for automated assembly
n Small footprint size (1210) and low profile for space-constrained mobile applications
n Ultra-low resistance, quick response
n RoHS compliant*
n Agency recognition:
WARNING Cancer and Reproductive Harm - www.P65Warnings.ca.gov
MF-NSMF Series - PTC Resettable Fuses
Product Dimensions
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
MF-USML/X Series – Low Ohmic PTC Resettable Fuses
Terminal material:
ENIG-plated terminals
Recommended Pad Layout
2.5 ± 0.1
(.098 ± .004)
2.0 ± 0.1
(.079 ± .004)
1.0 ± 0.05
(.039 ± .002)
1.0 ± 0.05
(.039 ± .002)
Bottom View
D E
A
B
C
Top View Side View
Thermal Derating Table - Ihold (Amps)
Model Ambient Operating Temperature
-40 °C -20 °C 0 °C 23 °C 40 °C 50 °C 60 °C 70 °C 85 °C
MF-USML175/12 2.57 2.33 2.07 1.75 1.49 1.34 1.24 1.00 0.88
MF-USML200/12 2.94 2.65 2.35 2.00 1.70 1.53 1.42 1.14 1.00
MF-USML260/12 3.82 3.46 3.07 2.60 2.21 1.95 1.85 1.48 1.30
MF-USML300/12 4.41 3.99 3.54 3.00 2.55 2.30 2.13 1.71 1.50
MF-USML350/12 5.10 4.65 4.13 3.50 2.98 2.65 2.50 2.00 1.75
MF-USML380/12 5.59 5.05 4.48 3.80 3.23 2.95 2.70 2.17 1.90
MF-USML400/12 5.80 5.25 4.70 4.00 3.40 3.10 2.80 2.28 2.00
MF-USML450/12 6.30 5.65 4.95 4.50 3.83 3.40 2.95 2.50 2.05
MF-USML500/12 7.00 6.25 5.50 5.00 4.25 3.75 3.25 2.75 2.25
MF-USML550/12 7.70 6.90 6.05 5.50 4.68 4.15 3.60 3.05 2.40
MF-USML175/12 ~ MF-USML260/12 = 5000 pcs. per reel
MF-USML300/12 ~ MF-USML550/12 = 3500 pcs. per reel
Model A B C D E
Min. Max. Min. Max. Min. Max. Min. Min. Max.
MF-USML175/12
3.00
(0.12)
3.43
(0.14)
2.35
(0.09)
2.80
(0.11)
0.40
(0.016)
0.80
(0.031)
0.25
(0.010)
0.05
(0.002)
0.45
(0.018)
MF-USML200/12
MF-USML260/12
MF-USML300/12
3.00
(0.12)
3.43
(0.14)
2.35
(0.09)
2.80
(0.11)
0.60
(0.024)
1.20
(0.047)
0.25
(0.010)
0.05
(0.002)
0.45
(0.018)
MF-USML350/12
MF-USML380/12
MF-USML400/12
MF-USML450/12
MF-USML500/12
MF-USML550/12
Packaging Quantity
DIMENSIONS: MM
(INCHES)
Applications
n Li-ion battery pack protection
n Power delivery port protection
n Higher voltage withstand
n PC motherboards – Plug & Play protection
n Mobile phones – battery & charging protection
n USB port protection
n Game console port protection
3312 - 2 mm SMD Trimming Potentiometer
MF-USML/X SERIES, REV. A, 03/19
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
MF-USML/X Series – Low Ohmic PTC Resettable Fuses
Typical Part Marking
Represents total content. Layout may vary.
Solder Reow Recommendations
Notes:
• MF-USML/X models cannot be wave soldered or hand soldered.
Please contact Bourns for soldering recommendations.
• All temperatures refer to topside of the package, measured on the
package body surface.
• If reow temperatures exceed the recommended prole, devices may
not meet the published specications.
• Compatible with Pb and Pb-free solder reow proles.
• Excess solder may cause a short circuit. Please refer to the Multifuse®
Polymer PTC Soldering Recommendation guidelines.
How to Order
MF - USML 400 / 12 - 2
Multifuse®
Product Designator
Series
USML = 1210 Low Ohmic
Surface Mount Component
Hold Current, Ihold
175 - 550 (1.75 Amps - 5.50 Amps)
Maximum Voltage, Vmax
12 = 12 Volts
Packaging
-2 = Tape and Reel
Packaged per EIA 481
PART IDENTIFICATION:
MF-USML175/12 = H12
MF-USML200/12 = J12
MF-USML260/12 = N12
MF-USML300/12 = P12
MF-USML350/12 = S12
MF-USML380/12 = V12
MF-USML400/12 = U12
MF-USML450/12 = X12
MF-USML500/12 = Y12
MF-USML550/12 = 512
MANUFACTURING DATE CODE IS
LOCATED ON PACKING LABEL.
U12
Temperature of Lead/Pad Junction
Process Materials Temperature Time
Description Interval
1. Apply solder paste to • Sn 96.5 / Ag 3.0 / Cu 0.5 Room temperature
test board (8 - 10 mil thick) Alloy water soluble or no
clean solder paste
(see note 1)
• single sided epoxy glass
(G10) (UL approved)
•PC board approx. 4x4x.06 in.
2. Place test units onto board 6 units/board
3. Ramp up Convection oven (see note 2) 2.5 °C ± 0.5 °/sec.
4. Preheat (TS.ces 03 ± 09C° 091 ot C° 051)
5. Time above liquidus (TL.ces 09-06C° 022)
6. Peak temperature (TP° 5-/° 0+ C° 052)
10-20 sec. within
5 °C of peak
.ces/C° 5.0 ± C° 3erutarepmet mooRnwod pmaR.7
(see note 2)
8. Cleaning water clean profile High pressure deionized 72 °F to 160 °F As required
water 65 PSI max. (22 °C to 71 °C)
Inspect solder joint to determine if solder joint is
acceptable (i.e. exhibits wetting of joint’s surface).
Use the following criteria (ref. acceptability of printed
board assemblies, IPC-A-610):
A) Acceptable (see Figure 1)
(1) The solder connection wetting angle (solder to
component and solder to PCB termination)
does not exceed 90 °.
(2) Solder balls that do not violate minimum
electrical clearances and are attached
(soldered) to a metal surface.
B) Unacceptable (see Figure 2)
(1) Solder connection wetting angle exceeding
90 °.
(2) Incomplete reflow of solder paste.
(3) Dewetting.
If unacceptable, determine cause and correct prior to
next run.
NOTES:
1. Water soluble solder paste only above 100K.
2. Refer to ref. temperature profile. Temperature at
lead/pad junction with “K” type thermocouple.
3. Units that are board mounted for environmental
testing must see a peak temperature in the reflow
zone, as specified. This is to ensure that all test
units will see “worst case conditions”.
4. Ramp down rate to be measured from 245 °C to
150 °C.
5. Process Description 8 does not apply to open
frame trimmers.
(Derived using 6-zone Convection Oven)
TP
TP
tp
ts
T TO
RAMP-UP L
TL
tL
25
Ts max
Ts min
PREHEAT
Temperature
Time
CRITICAL ZONE
RAMP-DOWN
t 25 °C TO PEAK
Prole Feature Pb-Free Assembly
Average Ramp-Up Rate (Tsmax to Tp) 3 °C / second max.
PREHEAT:
Temperature Min. (Tsmin)
Temperature Max. (Tsmax)
Time (Tsmin to Tsmax) (ts)
150 °C
200 °C
60~180 seconds
TIME MAINTAINED ABOVE:
Temperature (TL)
Time (tL)
217 °C
60~150 seconds
Peak Temperature (Tp)260 °C
Time within 5 °C of Actual Peak Temperature (tp) 20~40 seconds
Ramp-Down Rate 6 °C / second max.
Time 25 °C to Peak Temperature 8 minutes max.
MF-NSMF Series - PTC Resettable Fuses
MF-USML/X Series – Low Ohmic PTC Resettable Fuses
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
Asia-Pacic: Tel: +886-2 2562-4117 • Email: asiacus@bourns.com
EMEA: Tel: +36 88 885 877 • Email: eurocus@bourns.com
The Americas: Tel: +1-951 781-5500 • Email: americus@bourns.com
www.bourns.com
Packaging Specications
12.0 ± 0.30
(.472 ± .012)
0.65 ± 0.10
(.026 ± .004)
K0
K0
MF-USML175/12 ~ MF-USML260/12
1.10 ± 0.10
(.043 ± .004) MF-USML300/12 ~ MF-USML550/12
4.0 ± 0.10
(.157 ± .004)
2.0 ± 0.05
(.079 ± .002)
15.4*
(.606)
50
(1.97)
MIN.
HUB DIA.
1.75 ± 0.10
(.069 ± .004)
4.0 ± 0.10
(.157 ± .004)
2.90 ± 0.10
(.114 ± .004)
10.25
(.404)
390
(15.35)
3.50 ± 0.10
(.138 ± .004)
5.50 ± 0.05
(.216 ± .002)
4.5
(.177) MAX.
0.6
(.024) MAX.
0.1
(.004) MAX.
COVER
TAPE
1.50 +0.1 / -0
(.059 +.004 / -0) DIA.
TYP.
MAX.
185
(7.283) MAX.
*MEASURED AT HUB
LEADER MIN.
160
(6.30)
TRAILER MIN.
12.4 +1 / -0*
(.488 +.039 / -0)
DIMENSIONS: MM
(INCHES)
MF-USML/X Series per EIA 481
3312 - 2 mm SMD Trimming Potentiometer
Application Notice
MFAN 12/18
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
Bourns® Multifuse® PPTC Resettable Fuses
• Users are responsible for independent and adequate evaluation of Bourns® Multifuse® Polymer PTC devices in the user’s
application, including the PPTC device characteristics stated in the applicable data sheet.
• Polymer PTC devices must not be allowed to operate beyond their stated maximum ratings. Operation in excess of such
maximum ratings could result in damage to the PTC device and possibly lead to electrical arcing and/or re. Circuits with
inductance may generate a voltage above the rated voltage of the polymer PTC device and should be thoroughly evaluated
within the user’s application during the PTC selection and qualication process.
• Polymer PTC devices are intended to protect against adverse effects of temporary overcurrent or overtemperature
conditions up to rated limits and are not intended to serve as protective devices where overcurrent or overvoltage conditions
are expected to be repetitive or prolonged.
• In normal operation, polymer PTC devices experience thermal expansion under fault conditions. Thus, a polymer PTC
device must be protected against mechanical stress, and must be given adequate clearance within the user’s application to
accommodate such thermal expansion. Rigid potting materials or xed housings or coverings that do not provide adequate
clearance should be thoroughly examined and tested by the user, as they may result in the malfunction of polymer PTC
devices if the thermal expansion is inhibited.
• Exposure to lubricants, silicon-based oils, solvents, gels, electrolytes, acids, and other related or similar materials may
adversely affect the performance of polymer PTC devices.
• Aggressive solvents may adversely affect the performance of polymer PTC devices. Conformal coating, encapsulating,
potting, molding, and sealing materials may contain aggressive solvents including but not limited to xylene and toluene,
which are known to cause adverse effects on the performance of polymer PTCs. Such aggressive solvents must be
thoroughly cured or baked to ensure their complete removal from polymer PTCs to minimize the possible adverse effect
on the device.
• Recommended storage conditions should be followed at all times. Such conditions can be found on the applicable data
sheet and on the Multifuse® Polymer PTC Moisture/Reow Sensitivity Classication (MSL) note:
https://www.bourns.com/docs/RoHS-MSL/msl_mf.pdf
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C1753 05/17/18R