SparkFun Qwiic Mini dToF Imager – TMF8821

The SparkFun Qwiic Mini dToF TMF8821 Imager is a direct time-of-flight (dToF) sensor that includes a single modular package with an associated Vertical Cavity Surface Emitting Laser (VCSEL) from AMS. The dToF device is based on Single Photon Avalanche Photodiode (SPAD), time-to-digital converter (TDC) and histogram technology to achieve a 5000mm detection range. Due to its lens on the SPAD, it supports 3×3, 4×4, and 3×6 multizone output data and a very wide, dynamically adjustable field of view. A multi-lens-array (MLA) inside the package above the VCSEL widens up the FoI (field of illumination). All processing of the raw data is performed on-chip and the TMF8821 provides distance information together with confidence values on its I2C interface. The high performance on-chip optical filter blocks most of the ambient light, and enables distance measurements in dark and sunlight environments.

To make it even easier to get your readings, all communication is enacted exclusively via I2C, utilizing our handy Qwiic system so no soldering is required to connect it to the rest of your system. However, we still have broken out 0.1”-spaced pins in case you prefer to use a breadboard. The TMF8821 offers two configurable GPIO pins and one enable (EN) pin, which are broken out as PTH pads. The board also includes a power LED and I2C pull-up resistors, each configurable via jumpers. This Mini version has a footprint that is half the size (0.5in. x 1.0in.) of our standard Qwiic Mini dToF TMF8821 Imager board. Additionally, we moved the Qwiic connectors to the back of the board. These design changes favor mounting applications where the TMF8821 sensor faces outward from an enclosure or chassis, and keeps your Qwiic cables cleanly tucked away.

This sensor is great for projects such as distance measurement for camera autofocus – Laser Detect Autofocus – LDAF (mobile phone), presence detection (computing and communication), object detection and collision avoidance (robotics), and light curtain (industrial).

Note: CLASS 1 LASER PRODUCT CLASSIFIED IEC 60825-1 2014.

Get Started with the Qwiic DTOF TMF8820X Hookup Guide

Important

We recommend a microcontroller with enough flash to run your program code. Sorry, Uno’s (or any development board using the ATmega328P) are out. We recommend choosing either an Artemis Thing Plus, ESP32 Thing Plus, or a comparable device as your development board.

Features

• Operating Voltage
  • 2.7V to 3.6V
  • (typically 3.3V via Qwiic cable)
• Current Consumption
  • 8µA (standby)
  • 57mA (active)
• AMS TMF8821 Multi-zone Time-of-Flight Sensor
  • Direct ToF technology with high sensitivity SPAD detection
  • 4×4 configurable multi-zone configuration with multi-object detection
  • Fast Time-to-Digital Converter (TDC) architecture
  • Sub-nanosecond light pulse
  • On-chip histogram processing
  • High performance on-chip sunlight rejection filter and algorithm
• Measurement Range: 10mm to 5000mm @ 30Hz
• Light Source: Class 1 940nm VCSEL
• Field of View: adjustable up to 63° diagonally
• Max Read Rate: up to 30Hz
• 2x Qwiic Connectors
• I²C Address: 0x41
• Operating Temperature Range
  • -30°C to +70°C
• Breakout Pads
  • 1x Ground
  • 1x Power
  • 1x I²C Port
  • 1x Interrupt
  • 2x GPIO
  • 1x Enable
• Power LED (configurable via jumper)
• I²C pull-ups (configurable via jumper)
• Board Dimensions: 0.5′ x 1.0′ (1.27cm x 2.54cm)

Resources

• Schematic
• Eagle Files
• Board Dimensions
• Hookup Guide
• TMF882X
  • Datasheet
  • Driver User Guide
  • Host Driver Communication
• Arduino Library
• GitHub Hardware Repo