Learning from the animal world:
The world´s first MEMS ultrasonic Time-of-Flight sensors

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Communication modelled on dolphins:
engineers have often – and very successfully – drawn inspiration from the animal world.

Ultrasound
Dolphins use ultrasound not only for communication, but for orientation too,
using their natural sonar system. The principle: the further away an object is,
the more time the echoes need to return after reflection. Dolphin sonar also allows conclusions to be drawn about the material composition of objects. Each object produces its own characteristic reflection spectrum.

Time-of-Flight (ToF)
Today, we are familiar with Time-of-Flight (ToF) sensors, such as those in drones and smartphones. Until now, infrared (IR) technology has been used for this application. By calculating signal propagation times, the sensor can determine the position of an object in relation to a device and, if necessary, trigger a programmed action. With the IR sensor, this function is implemented by means of a light pulse.

Unique – Ultrasound and ToF in one 3.5 x 3.5 mm sensor
TDK Chirp Microsystems has now developed a high-quality 3D sensor technology based on the sonar principle and combined it with ToF sensor technology.
 The Time-of-Flight (ToF) ultrasonic sensors CH101 and the CH201.
In the industry, they are currently the only MEMS-based sonar on a millimetre-sized chip.

Ranges from 4 cm up to 5 m
The range of the ToF ultrasonic sensors is 4 cm to 5 m. The field of view covers 180° with an accuracy of up to 0.2 mm.

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The ToF ultrasonic sensors have integrated a MEMS PMUT (Piezoelectric Micromachined Ultrasonic Transducer) with a power-efficient digital signal processor (DSP) ASIC. The whole thing comes in a small case size of 3.5 mm x 3.5 mm x 1.26 mm.

  CH101 CH201
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Reach 4 cm to 120 cm 20 cm to 500 cm
Power consumption 12 µA to 50 µA 14 µA to 247 µA
Accuracy 1,0 mmRMS @ 30 cm 0,2 mmRMS @ 1 m
Temperature range -40 ºC to 85 ºC
I2C Interface
Voltage 1,8 V (1,62 V to 1,98 V)
Case 3,5 x 3,5 x 1,26 mm 8-Pin LGA Case

While the CH101 provides very accurate distance measurement to targets up to 1.2 m, the CH201 is particularly well-suited for the measurement of distances up to 5 m.

Ideal for social distancing and industrial applications
The sensor masters many functions and algorithms for processing ultrasonic signals, giving you newly found flexibility in industrial design options for your development. With the new ToF ultrasonic sensors, you can implement distance measurement, presence and proximity sensing, object detection and avoidance and position detection with ease.

These sensors are able to detect targets of any nature in all lighting conditions. Even transparent/translucent objects such as glass are thus clearly detectable. The colour or whether the target is transparent is also distinctly recognised. With the new technology, you can implement a wide range of applications, such as obstacle avoidance, presence detection, robotics, security and surveillance, AR/VR, drones, liquid level detection, smart home/building and general IoT applications.

The sensor's wide field of view (FoV) can be customised and allows simultaneous distance measurements to multiple objects within the FoV. These adjustments can be implemented using acoustic enclosure options. They are available for download as a file here.

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Summary and conclusion
Whether social distancing or industrial applications: TDK Chirp Microsystems' MEMS ultrasonic ToF sensor solutions offer numerous advantages over optical IR ToF sensors:

  • Ultra-low power consumption
  • Precise distance measurement regardless of the size or colour of the target; even optically transparent objects such as windows and glass doors/walls are reliably detected
  • Insensitive to ambient noise
  • Works in all lighting conditions
  • Provides eye safety
  • Detection of objects in a field of view of up to 180°, allowing a single sensor to support room-scale measurements

Development boards and samples for a quick start

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We at GLYN are happy to support you in case of any questions and enquiries.
For example, we keep development boards and modules, as well as pure samples of the two components, CH101 and CH201, in stock for you. Call us or send us an email.

Analog

Tel.
+49 6126 590-388
Fax
+49 6126 590-188
aap@glyn.de

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