4mm Mini Circular Force Sensor

The 4mm Mini Circular Force Sensor is a compact force-sensitive resistor designed to detect touch, squeezing, and physical pressure in electronic circuits. It interfaces easily with development boards like Arduino and Raspberry Pi, making it well suited for students, hobbyists, and makers building wearable tech or robotics prototypes.

Compact circular sensing area

The sensor features a 4mm (0.16 inch) diameter active sensing area on a slim flexible strip measuring 1.75 inches long by 0.28 inches wide. Its small form factor makes it suitable for integration into tight spaces and wearable projects.

Pressure-dependent resistance response

Resistance drops as force is applied to the sensing pad, transitioning from greater than 1MΩ when untouched down to 2.5kΩ under full pressure. This analogue resistance variation allows microcontrollers to easily track changes in applied force.

Breadboard-friendly connection pins

Two connector pins extend from the base of the sensor with a standard 0.1-inch pitch. This allows direct plug-in use with standard solderless breadboards and prototyping headers without soldering.

Qualitative touch and squeeze detection

This sensor is ideal for detecting whether an object is being grasped, tapped, or squeezed. Because it is designed for qualitative pressure sensing rather than high precision, it should not be used as an accurate weight scale.

Package contents

Includes one small force sensitive resistor component ready for immediate prototyping.

Downloads & documentation

• DataSheet-FSR400-Layout2
• Integration Guide & Evaluation Parts Catalog With Suggested Electrical Interfaces