SparkFun Qwiic dToF Imager - TMF8821

The SparkFun Qwiic dToF TMF8821 Imager is a highly advanced sensor that uses direct time-of-flight (dToF) technology. This compact device incorporates a Vertical Cavity Surface Emitting Laser (VCSEL) from AMS and is based on Single Photon Avalanche Photodiode (SPAD), time-to-digital converter (TDC) and histogram technology. With these features, it achieves an impressive detection range of 5000mm. The sensor also supports 3x3, 4x4, and 3x6 multizone output data thanks to its lens on the SPAD, and boasts a dynamically adjustable field of view. A multi-lens-array (MLA) above the VCSEL further broadens the field of illumination. The TMF8821 processes all raw data on-chip, providing distance information along with confidence values on its I²C interface. Its high-performance on-chip optical filter effectively blocks most ambient light, enabling accurate distance measurements in both dark and sunlight environments.

The SparkFun Qwiic dToF TMF8821 Imager is designed for ease of use. All communication is carried out exclusively via I²C, using the convenient Qwiic system, which eliminates the need for soldering when connecting it to your system. The device also features 2.54mm-spaced pins for those who prefer using a breadboard. The TMF8821 comes with two configurable GPIO pins and one enable (EN) pin, all of which are broken out as PTH pads. The board also includes a power LED and I²C pull-up resistors, each configurable via jumpers. The device measures 2.54cm x 2.54cm, adhering to the Qwiic Standard size.

The sensor is an excellent choice for a variety of applications. It can be used for distance measurement for camera autofocus in mobile phones, presence detection in computing and communication devices, object detection and collision avoidance in robotics, and light curtains in industrial settings. Please note that this is classified as a CLASS 1 LASER PRODUCT according to IEC 60825-1 2014.

The SparkFun Qwiic Connect System is a comprehensive ecosystem of I²C sensors, actuators, shields and cables designed to make prototyping faster and less error-prone. All Qwiic-enabled boards use a common 1mm pitch, 4-pin JST connector, which reduces the amount of required PCB space. The polarized connections ensure that you can’t connect it incorrectly.

For the best results, it is recommended to use a microcontroller with sufficient flash to run your program code. Development boards using the ATmega328P, such as Uno's, are not suitable. It is suggested to opt for either an Artemis Thing Plus, ESP32 Thing Plus, or a comparable device as your development board.

The SparkFun Qwiic dToF TMF8821 Imager comes with a range of features, including an operating voltage of 2.7V to 3.6V, a current consumption of 8µA (standby) and 57mA (active), and a measurement range of 10mm to 5000mm at 30Hz. The sensor uses a Class 1 940nm VCSEL light source, and offers a field of view adjustable up to 63° diagonally. It has a maximum read rate of up to 30Hz, and operates within a temperature range of -30°C to +70°C. The board also includes 1x Ground, 1x Power, 1x I²C Port, 1x Interrupt, 2x GPIO, and 1x Enable breakout pads.