World s first MEMS ultrasonic time-of-flight sensors

Transcription

1 Technologies & Products Press Conference 2018 World s first MEMS ultrasonic time-of-flight sensors Miniature high-performance range finding, presence detection and more Dr. David Horsley CTO Chirp Microsystems, Inc. A TDK Group Company Berkeley, CA, USA November 14, 2018

2 Ultrasonic sensing today Measure distance by time-offlight of an ultrasonic pulse Use multiple sensors to find object location (left, right, center ) Sense range to avoid objects and prevent collisions Detect human proximity and presence Automotive Automated guided vehicles Robotics Communication devices Drones Consumer robots CC 11/18 2

3 Ultrasonic sensors offer the best performance for range finding applications Advantages of ultrasonic ToF sensors vs. infrared ToF sensors Power consumption Sensitivity to lighting Detect dark or transparent objects Range noise Up to 500 times lower power consumption Range and accuracy not affected by ambient light or sunlight Sense any color target and windows, mirrors Up to 100 times lower noise Field-of-view (FoV) Up to 5 times wider CC 11/18 3

4 The new Chirp ultrasonic ToF sensor Sonar on a chip Ultrasound engine Main features Miniature size up to 1000 times smaller than conventional solutions Ultra-low power consumption (<15 µw) up to 100 times lower than conventional solutions Measuring range of 1 cm to 500 cm Very low noise range measurement of <1 mm RMS Wide field-of-view (FoV) up to 180 Integrated DSP chip for ultrasonic signal processing I2C Interface CC 11/18 4

5 MEMS ultrasonic ToF sensor specifications Specification CH-101 CH-201 Features & benefits Range, proximity, presence and gesture sensor in one Low always-on power High accuracy Programmable operating range Fast response time Wide and customizable FoV to customer requirements Insensitive to ambient light or color of objects Dimensions 3.5 mm x 3.5 mm x 1.25 mm Operating range 1.2 m 5 m Voltage Interface 1 sample/s and max. range 30 samples/s and max. range 1.8 V I2C 12 µa 20 µa 110 µa 330 µa Sample rate 1 m 5 m FoV 180 Range noise 1 mm 30 cm 0.2 mm 1 m CC 11/18 5

6 SiP with wide range of programmable functionality CH-101 and CH-201 are systems in package (SiP) with Piezoelectric micromachined ultrasonic transducer (PMUT) and Programmable system-on-chip (SoC) for all ultrasonic signal processing Ultrasonic pulse PMUT Programmable firmware for many functionalities, such as range-finding, proximity sensing and presence detection CC 11/18 6

7 Easy to interface to microcontrollers Features CH-101 and CH-201 sensors feature an I2C interface and operate from a 1.8 V supply Multiple sensors can share the same I2C bus CH-101 and CH-201 are pin-compatible and have the same API 1.8V AVDD VDD 0.1µF 7 CH-x01 CH VSS 3 SDA 2 SCL 8 RESET_N 1 INT PROG 4 2k2 2k2 10k 1.8V VDD Microcontroller SDA (Master) SCL (Master) GPIO GPIO GPIO GND Platform-independent C driver software helps customers with embedded software development CC 11/18 7

8 CH-201 ultrasonic ToF sensor performance 5000 Range measurement up to 5 m Range (mm) vs. Stage Distance Field of view (FoV) with narrow FoV housing Range (mm) samples at each distance (noise is too small too see) Target distance (mm) Range and FoV can be optimized with customized housings serving as apertures CC 11/18 8

9 CH-201 range and range noise Range cm Range noise vs. target range 6 ±0.35 mm 1σ 5 Range noise (mm) Corner reflector target Wall target Target distance (cm) Range (m) Noise up to 100x lower than competing IR ToF sensors at 120 cm range CC 11/18 9

10 Solutions from component to system level Unique sensor components On-chip sensing algorithms Complete system solutions Transmit burst Time of flight Echo from target Application-specific software enables Fast time to market Design of solutions with multiple Chirp sensors Piezoelectric micromachined ultrasonic transducer (PMUT) Ultrasound SoC Custom package Programmable SoC enables customized sensing CC 11/18 10

11 6-DoF controller reference design Features & Benefits Provides 6-DoF controller tracking based on sensor fusion Fuses ultrasonic ToF with IMU acceleration/rotation rate for lowlatency, high accuracy tracking Mobile-ready (no base station required) Near zero computation load Very low power consumption Works in any lighting condition Hand-held controller Chirp Chirp Chirp CH-101 CH-101 CH-101 (1 or more) (1 or more) (1 or more) Cortex-M0 MCU InvenSense IMU 2.4 GHz RF link Chirp embedded software Ultrasound Head-mounted display 2.4 GHz RF link Chirp fusion engine software Chirp Chirp Chirp CH-101 CH-101 CH-101 (1 or more) (1 or more) (up to 6) Apps processor InvenSense IMU CC 11/18 11

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