MF-FSML/X Series - Low Ohmic PTC Resettable Fuses

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Usersshouldverifyactualdeviceperformanceintheirspecificapplications.

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Solder Reflow Recommendations

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

.

c

e

s

0

3

±

0

9

C

°

0

9

1

o

t

C

°

0

5

1

)

5. Time above liquidus (TL

.

c

e

s

0

9

-

0

6

C

°

0

2

2

)

6. Peak temperature (TP

°

5

-

/

°

0

+

C

°

0

5

2

)

10-20 sec. within

5 °C of peak

.

c

e

s

/

C

°

5

.

0

±

C

°

3

e

r

u

t

a

r

e

p

m

e

t

m

o

o

R

n

w

o

d

p

m

a

R

.

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

t L

25

Ts max

Ts min

PREHEAT

Time

CRITICAL ZONE

RAMP-DOWN

t 25 °C TO PEAK

Notes:

• MF-FSML/X models are intended for reflow soldering (including, but

not limited to heating plate, hot air, IR, nitrogen, and vapor phase).

• Wave soldering is permissible only if the device is on the top of the

PCB, opposite the heat source.

• Hand soldering is not recommended for these devices.

• All temperatures refer to the topside of the device, measured on the

device body surface.

• If reflow temperatures exceed the recommended profile, devices may

not meet the published specifications.

• Compatible with Pb and Pb-free solder reflow profiles.

• Excess solder may cause a short circuit.

• Please refer to the Multifuse® Polymer PTC Resettable Fuse Soldering

Recommendations document for more details.

Profile Feature

Pb-Free Assembly

3 °C / second max.

PREHEAT:

150 °C

200 °C

60~180 seconds

TIME MAINTAINED ABOVE:

217 °C

60~150 seconds

260 °C

20~40 seconds

Ramp-Down Rate

6 °C / second max.

Time 25 °C to Peak Temperature

8 minutes max.

How to Order

MF - FSML 050 / 6 - 2

Product Designator

Series

FSML = 0603 Low Ohmic

Surface Mount Component

Hold Current, Ihold

035 - 300 (0.35 Amps - 3.00 Amps)

Maximum Voltage, Vmax

6 = 6 Volts

8 = 8 Volts

Packaging

-2 = Tape and Reel

Packaged per EIA 481

Typical Part Marking

No marking.