4 Pin U Type Tact Switch – Compact 3×4×2mm SMD Tactile Button

The TS-1185T4UM is a 3×4×2mm tact switch — a compact momentary push-button component developed for electronic products that require tactile feedback without taking up unnecessary PCB space. With a 3mm × 4mm footprint and 2mm height, this 4 pin U type tactile switch is suitable for compact control interfaces, handheld electronics, consumer devices, IoT equipment, and other space-constrained PCB assemblies.

This 4 pin U type SMD tact switch features a four-pin U-type configuration that provides a stable surface-mount arrangement while maintaining the compact form factor required by modern electronic designs. The switch is rated at 50mA and DC 12V and is available with two operating-force options: 180gf and 260gf. These options allow designers to select a lighter or firmer tactile response according to the requirements of the user interface.

With a travel of 0.15±0.10mm and an operating-life option of up to 100,000 cycles, this 3×4 SMD tact switch is suited to applications where repeated mechanical input is expected. Manufactured in an ISO 9001:2015 certified facility, this switch is fully compliant with RoHS 3 and REACH regulations.

Below are the complete specifications for the 4 pin U type SMD tact switch TS-1185T4UM, covering electrical, mechanical, and environmental ratings.

Specifications should be verified against the latest product drawing and engineering documentation before production release. Electrical performance depends on the complete circuit design and load conditions.

A 4 pin U type tactile switch is a momentary switching device. In its normal state, the switching circuit remains open. When the actuator is pressed, the internal contact mechanism changes state and allows the connected circuit to register the button input. When the actuator is released, the mechanism returns to its normal state.

The four-pin arrangement should not be interpreted simply as four independent switching channels. Depending on the internal construction, some terminals may form electrically common pairs. For that reason, engineers should use the product’s electrical diagram or datasheet rather than assuming pin connectivity from the external appearance alone.

In a typical digital interface, the switch can be used to provide a momentary input to a microcontroller or other control circuit. A suitable pull-up or pull-down arrangement can be used to establish a defined logic state when the button is not pressed. Mechanical switch bounce should also be considered in firmware or hardware design when clean digital transitions are required.

For a broader explanation of tactile switch construction and operation, engineers can also review our tactile switch working principle guide.

Selecting a 4 pin U type tact switch should begin with the mechanical requirements of the PCB rather than with the component name alone. Several products can have similar dimensions while using different terminal configurations, operating forces, or electrical ratings.

1. Check the PCB Footprint

Confirm the switch body dimensions, terminal positions, pad spacing, and recommended land pattern. This 3×4×2mm tact switch requires careful footprint design for reliable soldering.

2. Confirm the Pin Configuration

Verify that the selected component matches the required four-pin U-type arrangement. Do not rely solely on the number of visible terminals; always compare the electrical diagram and mechanical drawing.

3. Select the Operating Force

Consider whether the product requires a light or firm tactile response. The 180gf and 260gf options provide different user experiences and should be evaluated with the actual enclosure and button cap.

4. Check Travel and Mechanical Clearance

Make sure the actuator has sufficient clearance to operate correctly. The surrounding housing, decorative panel, or external button should not prevent the switch from reaching its intended travel.

5. Match the Electrical Rating

The rated 50mA and DC 12V specification should be compared with the actual circuit conditions. This 4 pin U type SMD tact switch should not be selected solely because its mechanical dimensions fit the board.

6. Consider Expected Operating Life

Estimate the number of button operations expected over the product’s service life. Applications with frequent daily operation may justify selecting the higher 100,000-cycle option.

Need a different configuration? Explore our full tactile switch product range.

Size and terminal configuration are useful starting points when comparing tactile switches. Vistar’s tactile switch range includes several footprints and configurations, allowing engineers to select a component according to the available PCB area and required mechanical interface.

If the design requires a smaller footprint, compare this product with our 3×4×2mm SMD tactile switch. For a larger four-pin option, see our 4.5mm SMD tact switch. Engineers looking for another U-type format can also review the 6.2mm 4-pin U-type tactile switch.

What Is a 4 Pin U Type Tact Switch?

A 4 pin U type tact switch is a compact momentary tactile switch with a four-pin U-type terminal configuration designed for surface-mount PCB assembly. The TS-1185T4UM features a 3×4×2mm package, providing a space-saving solution for electronic products where board space is limited. This 3×4×2mm tact switch is suitable for consumer electronics, IoT devices, portable equipment, and embedded systems where reliable momentary switching is required.

The U-type configuration refers to the terminal arrangement where the pins extend from the switch body in a U-shaped pattern. This design provides stable PCB mounting and reliable electrical connections in a compact form factor. The 4-pin configuration offers enhanced PCB retention compared to 2-pin alternatives.

4 Pin U Type Tactile Switch — Circuit and Configuration

A 4 pin U type tactile switch is a momentary switching device that provides temporary electrical contact when pressed. The four pins are arranged in a U-type pattern — two electrical contacts and two mechanical anchor pins. Depending on the internal construction, some terminals may form electrically common pairs. Engineers should use the product’s electrical diagram rather than assuming pin connectivity from the external appearance alone.

This 4 pin U type SMD tact switch is designed for automated SMT assembly and provides stable PCB retention through its 4-pin configuration. The U-type design is particularly suitable for compact PCB layouts where space efficiency is important.

3×4 SMD Tact Switch — Selection Considerations

When selecting a 3×4 SMD tact switch for your PCB design, consider the footprint, operating force, travel, electrical rating, and expected operating life. The 3×4×2mm footprint is ideal for space-constrained designs where larger tactile switches cannot fit. The 0.15mm travel provides a crisp tactile response with minimal actuation distance. The 50mA/12V rating is suitable for standard low-voltage control circuits.

For products requiring frequent button operation, choose the 100,000-cycle option for extended reliability. For applications with lighter usage requirements, the 50,000-cycle option may be sufficient. The operating force selection — 180gf for lighter touch or 260gf for more deliberate actuation — should be matched to the user interface requirements.

Applications Across Industries

This 4 pin U type tactile switch is widely used across multiple industries. Consumer electronics use it for handheld devices, remote controls, and audio equipment. IoT and smart devices use it for reset, setup, and mode-selection functions. Portable electronic equipment uses it for handheld instruments where enclosure volume is limited. PCB user interfaces use it for power control, reset input, and menu navigation. Embedded systems and wearable electronics also benefit from the compact 3×4×2mm package.

Why Choose Vistar as Your Tactile Switch Supplier

Vistar Electronics is a trusted tactile switch manufacturer serving customers in consumer electronics, industrial automation, medical devices, and communication equipment. Our tactile switch lineup covers 3×4mm, 4.5×4.5mm, 6×6mm, and 12×12mm configurations with various operating forces and mounting options.

With ISO 9001:2015 certification and a commitment to continuous improvement, Vistar is your reliable partner for high-quality switching solutions. For more technical resources, including PCB layout guidelines and switch selection guides, visit our technical blog or contact our engineering support team directly.

Explore our full range of tactile switches and related content:

• Tactile Switches — Full Product Collection
• 3×4×2mm SMD Tactile Switch
• 4.5mm SMD Tact Switch
• How Does Tact Switch Work?