SparkFun will be closed Monday 7/4/2022 for the 4th of July holiday. Orders placed after 2 pm MT on Friday 7/1/2022 will be processed on Tuesday 7/6/2022. SparkFun Support will also resume on Tuesday 7/6/2022. Have a safe holiday!

Distance Sensor 2m (Qwiic) - RFD77402

The Qwiic Distance Sensor uses the new RFD77402 Time of Flight sensor. This sensor is special in that it uses an infrared VCSEL or vertical-cavity surface-emitting laser to measure the amount of time it takes to bounce off a target. This allows low-cost millimeter readings up to 2 meters!

The VCSEL is a class 1 laser product so it is safe for almost all applications. The sensor doesn't emit visible light but most cell phones can see it!

We've written an RFD77402 Arduino library available for download through the integrated Arduino library manager.

The Qwiic system enables fast and solderless connection between popular platforms and various sensors and actuators. You can read more about the Qwiic system here. We carry 50mm, 100mm, 200mm, 500mm, and breadboard friendly Qwiic cables.

We do not plan to regularly produce SparkX products so get them while they’re hot!

Experimental Product: SparkX products are rapidly produced to bring you the most cutting edge technology as it becomes available. These products are tested but come with no guarantees. Live technical support is not available for SparkX products. Head on over to our forum for support or to ask a question.
  • Operating Voltage: 3.3V
  • Current: 7mA average at 10Hz
  • Measurement range: ~50mm to 2,000mm
  • Precision: +/-10%
  • Light source: VCSEL 850nm light source
  • Field of view: 55°
  • Field of illumination: 23°
  • Max read rate: 10Hz (in practice we've seen nearly 20Hz)
  • Dual Qwiic connectors for fast connection and optional daisy-chaining
  • I2C Interface up to 1MHz
  • On-board 4.7k pull up resistors (removable via jumper)

Distance Sensor 2m (Qwiic) - RFD77402 Product Help and Resources

Qwiic Distance Sensor (RFD77402) Hookup Guide

April 5, 2018

The RFD77402 uses an infrared VCSEL (Vertical Cavity Surface Emitting Laser) TOF (Time of Flight) module capable of millimeter precision distance readings up to 2 meters. It’s also part of SparkFun’s Qwiic system, so you won’t have to do any soldering to figure out how far away things are.


Looking for answers to technical questions?

We welcome your comments and suggestions below. However, if you are looking for solutions to technical questions please see our Technical Assistance page.

  • Member #482824 / about 5 years ago / 1

    Where can I find the datasheet for this chip that has the register map info in it?

    I'm trying to figure out exactly how to use the SetPeak and SetThreshold settings to have the sensor trigger the INT pin while in standby mode.

    I'm not exactly sure what the Peak & Threshold settings stand for.

    Any help is greatly appreciated!

  • this is reading up to only 2m, may I know what's the best distance sensor for 150m to 250m and more?

Customer Reviews

4 out of 5

Based on 1 ratings:

Currently viewing all customer reviews.


Works well, want more!!