Tiny time-of-flight ranging sensor has 2m range & improved speed

June 07, 2016 // By Graham Prophet
STMicroelectronics has added a faster and longer-range time-of-flight (ToF) ranging sensor, the second generation of its FlightSense technology, in the form of the VL53L0X laser-ranging module.

The VL53L0X extends the ToF measurement range to two metres, and is accurate to within ±3%. It is also faster, measuring the distance in under 30 msec, and energy-efficient, consuming 20 mW in active ranging mode and drawing 5 µA in standby. At 2.4 x 4.4 x 1 mm, it is also the smallest such device available, ST believes.

 

Unlike conventional infrared proximity sensors, the VL53L0X gives accurate distance measurement in millimetres, and is unaffected by the colour or reflectivity of the sensed target. Its FlightSense technology, used for laser-assisted camera auto-focus featured in several smartphones from top brands, can also distinguish movement towards or away from the sensor or from side to side. Distance is calculated internally and communicated over I ²C, minimizing demands on the system host controller.

 

The integrated eye-safe laser emits non-visible light of 940 nm wavelength (infrared), which eliminates the distracting red glow typically associated with other infrared proximity sensors and improves immunity to interference from external light sources. The sensor's digital architecture and automatic light compensation further enhance performance in high ambient-lighting levels.

 

The sensing capabilities of the VL53L0X can support a wide range of functions including gesture sensing or proximity detection for new innovative user interfaces, wall detection, cliff detection and collision avoidance for robotic appliances such as vacuum cleaners, as well as hands-free actuation of home appliances or washroom devices such as taps, soap dispensers, hand dryers, and flushers. Other applications include user-presence detection for laptops or monitors for power-on/off control, and drones.

 

The VL53L0X is supplied with a software API as well as full documentation and example source codeand is supported on the X-NUCLEO-53L0A1 expansion board, which can be connected to the family of STM32 Nucleo microcontroller boards for easy evaluation of the VL53L0X performance.

 

In a 12-pad reflow-compatible module, it is priced at $2.30 (1,000) pieces. For mass-production orders, minimum order quantity is 5,000