FSR402 Resistive Thin Film Pressure Sensor

FSR402 Resistive Thin Film Pressure Sensor is a robust, ultra-thin polymer thick film (PTF) device that exhibits a predictable decrease in resistance as the force applied to the active surface increases. This Force Sensitive Resistor (FSR) excels in human-machine interface (HMI) applications where designers require a compact and reliable method to detect physical touch or weight. Furthermore, its flexible construction and small form factor allow for seamless integration into curved surfaces or space-constrained enclosures. Consequently, this sensor provides a cost-effective alternative to complex load cells for non-precision force sensing. Therefore, you can easily implement the FSR402 into your next interactive project to capture tactile input with high durability and minimal circuitry.

Key Features:

• High Sensitivity: The sensor detects a wide range of force, from a light touch of 0.2N to a heavy press of 20N, providing a dynamic response for various user inputs.
• Ultra-Thin Profile: With a thickness of only 0.45 mm, the FSR402 fits into incredibly tight spaces where traditional mechanical switches cannot operate.
• High Durability: Engineered for longevity, this sensor withstands over 10 million actuations, ensuring consistent performance in high-traffic interactive devices.
• Simple Interface: The resistive output simplifies the drive electronics, usually requiring only a single voltage divider circuit to interface with a microcontroller ADC.
• Flexible Design: The polymer substrate offers enough flexibility to conform to slightly contoured surfaces without compromising sensor integrity.

Technical Specifications:

• Actuation Force: ≈ 0.2 N (20 g)
• Force Sensitivity Range: 0.2 N to 20 N (20 g to 2 kg)
• Non-Actuated Resistance: > 10 MΩ (Open Circuit)
• Force Resolution: Continuous (Analog)
• Repeatability: ±2% to ±5% (depending on load consistency)
• Hysteresis: ±10% (Typical)
• Operating Temperature: −30°C to +70°C

Mechanical Specifications:

• Active Area Diameter: 12.7 mm (0.5 inch)
• Total Thickness: 0.45 mm
• Substrate Material: Polyester (PET)
• Connector Type: 2-pin Male Solder Tabs (0.1 inch pitch)
• Tail Length: ≈ 39 mm

Dimensions:

• Overall Length: ≈ 56 mm
• Overall Width: ≈ 18 mm
• Sensor Diameter: 18.28 mm
• Pin Spacing: 2.54 mm (Standard breadboard compatibility)

Pinout and Wiring:

• Pin 1 (Terminal A): Connect to a stable voltage source (e.g., 5V or 3.3V).
• Pin 2 (Terminal B): Connect to an Analog-to-Digital Converter (ADC) pin on your microcontroller.
• Pulldown Resistor: Place a 10kΩ resistor between Pin 2 and Ground to create a voltage divider. However, you may adjust this resistor value to tune the sensitivity and output range of the sensor.

Datasheet Reference:

• Download Interlink Electronics FSR402 Datasheet

Commonly Used in:

• Musical Instruments: Electronic drum pads and velocity-sensitive MIDI keyboard controllers use these sensors for expressive play.
• Medical Devices: Applied in pressure-sensitive beds, smart insoles, and prosthetic touch feedback systems.
• Automotive Controls: Occupancy sensors and touch-sensitive interior panels leverage FSR technology for sleek, modern interfaces.

Applications:

• Touch Detection: Implementing reliable touch triggers in industrial control panels or consumer appliances.
• Weight Sensing: Creating simple scales or presence detection mats where high precision is not mandatory.
• Robotic Grippers: Providing tactile feedback to robotic fingers to prevent crushing delicate objects during manipulation.

Equivalent Models:

• Flexiforce A201: A high-performance thin-film sensor, however, it features a much narrower sensing tail.
• FSR 400: The smaller sibling of the FSR402, offering a 5mm active area for even more compact designs.
• DFRobot RP-C18.3-ST: A similar resistive pressure sensor often used in hobbyist electronics with comparable force ranges.

Package Includes:

• 1 x FSR402 Resistive Thin Film Pressure Sensor