Upgraded Human Radar Motion Switch

The Upgraded Human Radar Motion Switch is an advanced solid-state AC switching system designed to automate loads based on human presence. At the core of the system is the RCWL-0516 Microwave Radar Sensor, which utilizes Doppler radar technology to detect motion by emitting 3.2GHz electromagnetic waves and measuring frequency shifts in the reflected signals. This provides superior detection compared to traditional passive infrared (PIR) sensors, as it can penetrate thin non-metallic barriers and detect subtle movements. An integrated LDR (Light Dependent Resistor) acts as a photocell, allowing the system to differentiate between day and night conditions so that motion-triggered automation only occurs in low-light environments. Processing and control are handled by a microcontroller board such as the IndusBoard Coin V2, ESP32 DevKit v1, or Arduino Uno, depending on the specific build variant. When motion is registered alongside appropriate ambient light levels, the microcontroller triggers an optically isolated output path. This path utilizes the VO2223A-X007T Optotriac IC, which safely bridges the low-voltage logic circuitry from the high-voltage AC side while driving downstream loads. Powering the entire system is an LD05-23B05R2 AC-DC power supply module, complemented by filtering components like the 100nF Capacitor (C3) for noise suppression. Connections are managed cleanly via DB301V-3.5-2P-GN screw terminals and an FPC 24P connector, with 100-ohm and 120-ohm resistors appropriately configured for current limiting and signal integrity across the circuit layout.