The scenario
A dancer stepping on a force-sensing resistor changes its resistance, raising the base voltage of an NPN transistor and lighting an LED panel.
What is in this drawing
Read the decisions behind it.
01
Use an FSR in a voltage divider with a fixed pulldown resistor to convert pressure into a control voltage.
02
Drive the LED panel with an NPN BJT as a low-side switch.
03
Add a smoothing capacitor across the base pulldown to reduce flicker.
Reusable for interactive floor panels, pressure-sensitive mats, or any design where variable resistance controls an LED or small lamp load.
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