Datasheet
2
B3FS-4 SMD Tactile Switch
■ Precautions
Be sure to read the safety precautions common to all Tactile Switches for correct use.
● PCBs
If the PCBs are separated after mounting the Switch, particles
from the PCBs may enter the Switch. If PCB particles or foreign
particles from the surrounding environment, workbench, contain-
ers, or stacked PCBs become attached to the Switch, contact
failure may result.
● Soldering
1. General Precautions
Before soldering the Switch on a multilayer PCB, test to confirm
that soldering can be performed properly. Otherwise the Switch
may be deformed by the soldering heat on the pattern or lands of
the multilayer PCB.
Do not solder the Switch more than twice, including rectification
soldering. An interval of five minutes is required between the first
and the second soldering, or it may result in melting housing and
deterioration of operating characteristics.
2.Reflow Soldering (Surface Mounting)
Solder the terminals within the heating curve shown in the follow-
ing diagram.
Note: The above heating curve applies if the PCB thickness is 1.6 mm.
The peak temperature may vary depending on the reflow bath
used. Confirm the conditions beforehand.
Do not use an automatic soldering bath for surface-mounted
Switches. The soldering gas or flux may enter the Switch and
damage the Switch's plunger operation.
3. Manual Soldering
Soldering temperature: 350 degC max. at the tip of the soldering
iron Soldering time: 3 s max. for a 1.6-mm thick, single-side PCB
Before soldering the Switch on a PCB, make sure that there is no
unnecessary space between the Switch and the PCB.
● Washing
This switch cannot be washed.
Doing so will cause the washing agent, together with flux or dust
particles on the PCB, to enter the Switch, resulting in malfunc-
tion.
● Packaging Specifications for Embossed Taping
● RoHS Compliant
The “RoHS Compliant” designation indicates that the listed mod-
els do not contain the six hazardous substances covered by the
RoHS Directive.
Reference:
The following standards are used to determine compliance for
the six substances.
Lead: 1,000 ppm max.
Mercury: 1,000 ppm max.
Cadmium: 100 ppm max.
Hexavalent chromium: 1,000 ppm max.
PBB: 1,000 ppm max.
PBDE: 1,000 ppm max.
Precautions for Correct Use
Temperture (°C)
180
220
250 max.
Room
temperture
150
Preheating
Heating
Time (s)
60 to 120 Max.60
ø13.2
ø3
80
±2
16
±0.1
Reel (Material: PS)
Label
Tape drawing direction
Tape drawing direction
(29)
4
±0.1
(5.6)
2
A
24
11.5
1.75
ø1.5
+0.1
0
A
ALL DIMENSIONS SHOWN ARE IN MILLIMETERS.
To convert millimeters into inches, multiply by 0.03937. To convert grams into ounces, multiply by 0.03527.