LD2410B 24GHz Human Presence Sensor | Millimeter-Wave Radar with Bluetooth | Detects Motion & Stillness | Up to 5m Range | GPIO & UART

The LD2410B is a highly sensitive 24 GHz FMCW millimeter-wave radar designed for reliable indoor human presence detection. Unlike traditional PIR motion sensors, it detects not only movement but also static or minimally moving people (e.g. sitting or lying down) – making it ideal for smart home, automation, and IoT projects.

Highlights

• Presence detection even without movement – detects standing, sitting, and resting persons
• Range up to 5 m (adjustable) & detection angle ±60°
• Bluetooth configuration via app as well as UART configuration support
• Plug & Play – GPIO output (High = person detected) plus UART data output
• Resistant to environmental influences – independent of light, temperature, and humidity

Applications

• Smart home lighting control (presence instead of motion)
• Energy saving: automatically switch off devices/displays when no one is present
• Room and hallway automation, office, bathroom, bedroom
• Security & access control solutions (person detected / no person detected)

Technical Specifications

• Frequency: 24–24.25 GHz
• Technology: FMCW millimeter-wave radar
• Detection range: up to 5m (adjustable)
• Detection angle: ±60°
• Distance resolution: 0.75 m
• Power supply: 5 V DC
• Current consumption: approx. 79 mA (typical)
• Interfaces: GPIO (3.3 V logic), UART
• Default UART: 256000 baud, 8N1
• Dimensions: 7 mm × 35 mm

Pinout

• OUT: Status output (High = presence detected, Low = no presence)
• UART_TX: Serial TX
• UART_RX: Serial RX
• GND: Ground
• VCC: 5V supply

Installation Notes

• For best results, mount the sensor securely (avoid vibrations).
• The enclosure/radome should be transparent at 24 GHz (no metal or shielding materials).
• Moving interference sources (e.g. curtains, fans, large plants in airflow) may affect detection.