TR/SFT-3 Cooper/Bussmann, TR/SFT-3 Datasheet - Page 2

• Manufacturer Part Number: TR/SFT-3
• Description: FUSE 3.00A 125V FAST SMD TRON
• Manufacturer: Cooper/Bussmann
• Series: TRON® SFTr

Specifications of TR/SFT-3

• Fuse Type: Fast Acting
• Voltage - Rated: 125VAC, 125VDC
• Current: 3A
• Package / Case: Non-Standard SMD
• Size / Dimension: 0.294" L x 0.170" W x 0.120" H (7.47mm x 4.32mm x 3.05mm)
• Mounting Type: Surface Mount
• Melting I²t: 0.4359
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Operating Temperature: -
• Color: -
• Other names: 283-2434-2; TR-SFT-3

Figure 1
1.0 Materials
2.0 Markings
Body shall be permanently and legibly marked with BUSS
ampere rating, voltage rating and date code. Markings will not become illegible
or discolored when the parts are subjected to solvents normally used to remove
solder/flux, fingerprints, and other contaminants from printed circuit boards, as
tested per MIL-STD-202, Method 215F.
3.0 Trace Geometry Considerations
Trace geometry can affect fuse performance and should be considered when
applying any subminiature fuse. Figures 1 and 2 detail the trace geometry used
in generating this specification. Suitable trace geometry for a particular applica-
tion depends on fuse rating, current flow, and ambient temperature. Final deter-
mination of suitability for a specific application should be based on empirical
testing with all parameters involved. Printed circuit board is .096 inches thick,
epoxy glass with 1 ounce copper foil, coated with 300 micro inches of 60/40 tin
lead solder.
Note: Smaller than recommended trace width may
affect the fuse performance by providing additional heat and reducing carrying
capacity of the fuse.
4.0 Thermal Withstand Capability
Infrared Exposure. When the device is exposed to the time-temperature profile
detailed in Figure 3, the resistance of the device will not change by more than
5%, as measured after the device has dwelled at room temperature for at least
one hour.
Figure 3
IR Time-Temperature Profile
Vapor Phase Exposure. When the device is exposed for ten minutes to the
vapor produced by liquid fluorinert FC-5312 at 218°C, the resistance of the
device will not change by more than 5%, as measured after the device has
dwelled at room temperature for at least one hour.
Resistance to Soldering Heat. MIL-STD-202F, Method B. When device is
immersed in a 260°C soldering pot for 10 seconds, the resistance of the device
will not change by more than 5% as measured after the device has dwelled at
room temperature for at least one hour.
*Better Solderability. To eliminate solder ball extrusion and to provide
improved solderability in formed areas of leads, order part number
SFT-1J0367-amp. For 63mA - 10A fuses.
5.0 Mechanical Characteristics
Mechanical Shock. Fuse base shall not chip or crack when dropped from a
height of 48" onto a concrete surface.
Vibration. The fuse resistance shall return to within 10% of the original value
when the fuse is subjected to a frequency range cycle of one minute in each of
the three mutually perpendicular directions having a vibration amplitude of .06
inches peak to peak at a frequency of 10-55Hz. per MIL-STD-202F, Method 204
Condition A.
SMD TRON
For .170” x .294” (4.32mm x 7.47mm) Fuses
12-28-98
SB98107
25 C
Body Material: Thermoplastic, with a rating of 94V-O as defined by U.L.
Standard 94. Material has an oxygen index of 53% per ASTM D2863-77.
Lead Material: Base–Copper.
Detail A
175 C
2 min.
Rev. A
Barrier–Nickel (50-100 micro inches).
Finish–Electroplated Tin (400-500 micro inches with a
2-10% lead content).
3.5 min.
230 C
2 min.
®
250 C
The only controlled copy of this BIF document is the electronic read-only version located on the Bussmann Network Drive. All other
copies of this BIF document are by definition uncontrolled. This bulletin is intended to clearly present comprehensive product data
and provide technical information that will help the end user with design applications. Bussmann reserves the right, without notice,
to change design or construction of any products and to discontinue or limit distribution of any products. Bussmann also reserves
the right to change or update, without notice, any technical information contained in this bulletin. Once a product has been selected,
it should be tested by the user in all possible applications.
Surface Mount Fuses
25 C
.350"
.100"
000
Detail A
.055"
®
, catalog symbol,
.060"
Figure 2
.114"
Terminal Secureness. The fuse terminals shall not distort, and the fuse body
will not chip or crack when the fuse is placed on a printed circuit board and a
vertical downward force of 1/2 kilograms is applied to the top of the fuse for 10
seconds.
6.0 Packaging
All unit packaging material will be manufactured from static inhibiting materials.
Tape and reel packaging will comply with EIA Std 481-2. Tape width shall be
16mm and reel diameter 7 inches or 13 inches.
Packaging Code
TR/
TR1/ 2000 on a 13" reel, 16mm tape width
Figure 4
7.0 Load Cycling
Load cycling of the SMD TRON
resistances and voltage drops for cycling applications. Through measurement
of initial and final resistances, an assessment of the reliability of the fuse can be
predicted.
Test Conditions. A duty cycle of 60 seconds on at rated current and 60 sec-
onds off to make a total period of 120 seconds.
Other circuit parameters were:
Amplitude – 100% rated current
Rise Time – 36.8 microseconds
Ripple Average –15.9mA
System Voltage – 55 volts
Test Criteria. The fuse must complete 200,000 cycles without failure, then
resistance and voltage drop measurements are compared to initial measure-
ments, which cannot change by more than 5%.
Test Data:
Average Initial Resistance: 21.11 milli ohms
Average Final Resistance: 20.57 milli ohms
% Change: –2.55%
SFT Voltage Drop as a Percent of Rated Current (Typical)
.14"
.01"
.8
.7
.6
.5
.4
.3
.2
.1
.18
.16
.14
.12
.08
.06
.04
.02
0
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
.2
.1
0
500 on a 7" reel, 16mm tape width
10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
.31"
.06 " Dia.
A
Percent of Rated Current
A
Percent of Rated Current
.19"
.08"
®
.32"
was performed to observe the stability of the
.16"
.3"
.63"
.07"
Embossed carrier tape which
conforms to the EIA Standards
EIA481-2.
Carrier material black
conductive polystyrene,
Non-Conductive Tape Material.
Bussmann
SFT-.25
SFT-.5
SFT-.375
SFT-.75
SFT-1.5
SFT-2
SFT-3.5
SFT-2.5
SFT-4
SFT-3
SFT-10
SFT-5
SFT-1
SFT-7
BIF Doc #2005
Form No. SFT
SFT
Page 2 of 2
®
R