OMRON B3D_10

Ultra-low Profile Dome Key
B3D
Single-key Type Added to Series of B3DA
Ultra-low Profile Dome Arrays
• No soldering required. Attach directly to PCB to make an ultra-low
profile tactile switch. Construction provides strong resistance to
static electricity by having no soldered terminals.
• Matrix adhesive used to create highly dust-proof construction
with good ventilation.
• Lower profile, lighter weight, and crisp clicking action.
• Omron's unique circular contact action ensures a high level
of resistance to foreign matter.
• RoHS Compliant.
Application Examples
Use Dome Keys for the operating parts on various electronic devices that require low-profile controls, as follows:
• Operating switches with few mounted parts above PCBs.
(Example: Camera operating buttons)
• Small orders, where initial investment in Dome Arrays is not feasible.
(Example: Trial applications, commercial equipment, etc.)
• Applications requiring a single key only.
(Example: Reset buttons)
B3D-5112
2
-411
B3D
Specifications
Item
Model
B3D-4112
B3D-5112
Diameter of contact dome
4-mm dia.
5-mm dia.
Operating force (OF)
approx. 170 ± 50 gf (1.67± 0.49 N)
Releasing force (RF)
20 gf min. (0.2 N min.)
Pretravel (PT)
0.2 ± 0.1 mm
Height
0.3 ± 0.1 mm
Life expectancy
500,000 operations min.
Switching capacity
10 mA at 12 VDC (resistive)
Minimum permissible load
1 mA at 3 VDC (resistive)
Ambient operating temperature
-40 to 80°C (at 60% RH max.) with no icing or condensation.
Ambient storage humidity
10% to 90% (at 40°C max.)
Contact - base material
Stainless steel
Plating
Silver
1,000,000 operations min.
Note: The Dome Keys are sold in units of 500 (20 sheets, with 25 Dome Keys per sheet). Orders must be made in multiples of 500 Dome Keys.
Ultra-low Profile Dome Key
B3D
269
Structure
■ Circular Contact
PET film (white)
(with matrix adhesive)
Stainless steel
contact dome
(circular contact)
Polyurethane
rubber film (with adhesive)
When contact dome keys are attached to the PCB, any PCB dust or
foreign particles will tend to collect in the center of the key when it is
pressed. Therefore, poor contact occurs easily in keys that provide
contact at the center point only.
The circular contact construction provides contact along the circumference of
a circle, thus preventing poor contact by avoiding the center point.
Contact dome resistant to
foreign matter (circular contact)
Conventional models
■ Matrix Adhesive
The surface structure of this adhesive has grid-shaped slits, as
shown in the following cross-sectional diagram. These slits provide
both ventilation and dust-proofing, which is required for contact dome
operation.
Cylindrical protrusion
Cover film
15 µm
Matrix (acrylic)
adhesive: 25 µm
Slits
Contact at center point
Contact along
circle circumference
(circular contact)
Recommended Contact Form
4 mm Diameter Contact Dome (B3D-4112)
5 mm Diameter Contact Dome (B3D-5112)
6.2 dia.
5.2 dia.
1.8 dia.
Gold-plated nickel
2.3 dia.
0.4
0.4
1.2 2.0
Single-side PCB
2.8 dia.
Resist (30 to 50 µm)
3.8 dia.
Resist (30 to 50 µm)
6.2 dia.
Gold-plated nickel
Multilayer PCB
2.3 dia.
Multilayer PCB
2.8 dia.
270
1.2 2.0
Single-side PCB
5.2 dia.
1.8 dia.
Gold-plated nickel
Ultra-low Profile Dome Key
3.8 dia.
B3D
Gold-plated nickel
Recommended Operating Part Form
4 mm Diameter Contact Dome (B3D-4112)
5 mm Diameter Contact Dome (B3D-5112)
Resin
Resin
1 dia.
Entire
circumference: R 0.2
1.5 dia.
Entire
circumference: R 0.2
Dimensions
B3D-4112
Section A enlarged
Section A
(54)
25, 7.4 dia.
0.3
0.3
10
10
(54)
10
10
10
10
10
10
B3D-5112
Section A
(54)
25, 8.4 dia.
Section A enlarged
0.3
0.3
10
10
(54)
10
10
10
10
10
10
Ultra-low Profile Dome Key
B3D
271
PCB Pattern Diagrams
B3D-4112
B3D-5112
Precautions
■ Attaching to the PCB
■ Reflow Soldering
Remove the Dome Key from the sheet using tweezers or a vacuum
pick-up tool, and attach it above the contact on the PCB surface,
which has been wiped clean in advance. Press down on the top surface using an elastic material, such as urethane rubber, and a force
of 2.94 to 4.9 N. Place a positioning mark (circle) on the PCB for
easy positioning.
The Dome Key cannot withstand heat from reflow soldering. Always
perform reflow soldering before attaching the Dome Key to the PCB.
Make sure that the position of the Dome Key is aligned correctly
before use. Significant misalignment may result in short-circuits or
reduced sensitivity.
Note: The recommended vacuum pick-up tool is the Hozan P-835
Vacuum Pick with an M suction pad (7-mm dia.).
Do not reuse a B3D Dome Key that has been detached from the
PCB. Attach a new Dome Key to the PCB.
Do not touch the contact dome with bare hands, or with unclean
gloves. Doing so may damage the contact dome, which is the part
that comes in contact with the PCB.
272
Ultra-low Profile Dome Key
B3D
■ Washing
Do not wash the Dome Key. The Dome Key is not water-resistant and
must not be exposed to water or other liquids.
■ Common Precautions
Be sure to read the precautions common to all Tactile Switches,
contained in the Technical User’s Guide, “Tactile Switches, Technical
Information” for correct use.
MEMO
Ultra-low Profile Dome Key
B3D
All sales are subject to Omron Electronic Components LLC standard terms and conditions of sale, which
can be found at http://www.components.omron.com/components/web/webfiles.nsf/sales_terms.html
ALL DIMENSIONS SHOWN ARE IN MILLIMETERS.
To convert millimeters into inches, multiply by 0.03937. To convert grams into ounces, multiply by 0.03527.
OMRON ON-LINE
OMRON ELECTRONIC
COMPONENTS LLC
Global - http://www.omron.com
USA - http://www.components.omron.com
55 E. Commerce Drive, Suite B
Schaumburg, IL 60173
847-882-2288
Cat. No. X303-E-1
11/10
Ultra-low Profile Dome Key
Specifications subject to change without notice
B3D
Printed in USA