The TPE-500 is our smallest Shunt Mode Force Sensing Resistor (FSR), with a sensing zone measuring just 8mm in diameter and a total length of 16mm (plus housing).
 
FSR's are constructed in two layers of flexible polymer. One layer is printed with a proprietary force-sensing ink, the other with silver interdigitating electrodes. The two substrates are then positioned facing each other and adhered using a spacer adhesive around the circumference.
 
When a force is applied to the device the layers come into contact and a circuit is completed. As more force is applied resistance drops and more current flows.