MEMS ToF sensor supports a sensing range of 1 meter

By Majeed Ahmad, contributing writer

TDK claims to have launched the first commercially available MEMS-based ultrasonic time-of-flight (ToF) sensor for the internet of things (IoT), augmented reality (AR), virtual reality (VR), robotics, drones, automotive, consumer, and industrial applications. The CH-101 ToF sensor supports a maximum sensing range of 1 meter and can detect objects over a field of view of up to 180°, enabling a single sensor to support room-scale sensing, said TDK.

The CH-101  sensor, developed by Chirp Microsystems, a TDK company, utilizes a tiny ultrasonic transducer chip to send out a pulse of ultrasound and then listen for echoes returning from targets in the sensor’s field of view. After calculating the ToF, the sensor determines the location of an object relative to a device and triggers a programmed behavior.

The ToF sensor — measuring 3.5 × 3.5 mm — combines a MEMS ultrasonic transducer with a power-efficient DSP incorporated into a mixed-signal ASIC. It handles a variety of ultrasonic signal-processing functions, enabling a broad range of use cases that include range finding, presence and proximity sensing, object detection and avoidance, and position tracking.

According to TDK, the MEMS-based ultrasonic ToF sensor solution offers numerous advantages over optical ToF sensors. These include accurate range measurement regardless of target size or color, immunity to ambient noise, and the ability to operate in all lighting conditions.

Along with CH-101, TDK is offering the CH-201 ultrasonic ToF sensor for room-scale sensing applications. The CH-101 sensor is in mass production now, while Chirp’s CH-201 is currently shipping to select customers.