Both chips share a common 3.5x3.5mm package and the same ASIC for signal processing, but the piezoelectric micro-machined ultrasonic transducers (PMUT), the MEMS parts of the sensors are built differently, tuned for the different ranges, learned eeNews Europe.
"In fact, we have been sampling the CH101 for two years now and we realized we had never made a product announcement for it", told us David Horsley, Chirp Microsystems' CTO. "Chirp Microsystems was founded in 2013, the CH-101 is a 2nd generation design while the CH-201 is our third generation design. Our 4th generation of chips is being tested today, and with each design so far, we've improved our transmitter and receiver performance by 4X", Horsley told eeNews Europe during an interview.
The ASIC drives the MEMS array of silicon membranes to emit ultrasonic waves, which bounce off obstacles in their path and are detected back by the same membranes running in a microphone mode. The time interval (time-of-flight) between signal output and detection is what can be converted into a 2D depth map across a 180º field-of-view. According to Chirp Microsystems, the chips are the first commercially available MEMS-based ultrasonic ToF sensors and beat all other ToF solutions on small size and low power consumption.
The "Sonars on a chip" as Horsley describe them draw 100x less power and are a thousand times smaller than the best ultrasonic range finders used in today's automotive applications. They are not only small enough and low power enough to be implemented in smartphones and other wearable electronic applications, unlike infrared-based optical ToF sensor they do not require a direct optical paths, allowing engineers to design bezel-free smartphones with accurate gesture sensing.
But that's not all what there is on the company's roadmap.