Keynote Speakers

Capacitive sensors are extensively utilized for IoT applications due to their low noise and temperature dependence. They find can be used to sense a broad range of physical quantities, such as pressure, humidity, acceleration, gas molecules, and proximity. To read out such sensors and extract useful information, high performance capacitance-to-digital converters (CDCs) are required. Their design is quite challenging due to the many design tradeoffs that must be made between performance parameters such as energy efficiency, sensing resolution, and input range. In this talk, the basic principles of capacitive sensors, the design goals and tradeoffs of CDCs, and conventional circuit structures will first be reviewed. Then, more recent and advanced circuit structures and design techniques to improve energy efficiency, sensing resolution, and input range will be presented. Lastly, some future research directions in the design and application of CDCs will be discussed.

BJT-based temperature sensors are widely used because they can achieve high accuracy over a wide temperature range after a low-cost room temperature calibration. Such sensors have traditionally employed switched-capacitor (SC) readout circuits to consistently achieve inaccuracies below 0.2°C (3σ) from −55°C to 125°C. However, their inherent kT/C noise then limits the sensor’s resolution and energy efficiency. In principle, this penalty can be avoided by using Continuous-Time (CT) readout circuitry, but matching the accuracy of their SC counterparts has proved challenging. In this talk, we will review the emergence of accurate CT-readout circuits for BJT-based temperature sensors, and discuss recent advances in the state-of-the-art.

In the manufacturing industry, precision sensors are often required, whose analog outputs must then be conditioned and digitized by equally precise sensor interfaces. However, the volumes involved in such applications are usually too small to justify the development of custom ASICs, and so such interfaces must be realized with standard commercially-available components. In this talk, two case studies will be presented which illustrate how precision sensor interfaces can be realized by pushing the performance of standard components to their limits. The first case study involves the design and characterization of an interface circuit for a photo-diode, which must detect the amplitude of the light received from a modulated source over a wide dynamic range. The second case study involves the design and characterization of an interface circuit for a thermistor bridge, which must achieve µK resolution as well as a very low (sub-10mHz) flicker noise corner.

Magnetic field sensors can be used to detect angular, linear and even 3-D position, as well as rotational speed and direction. Such sensors should have a wide dynamic range, since they are often located close to a permanent magnet, and, because they need to be robust to external stray fields. For ease of use, such sensors should also have a digital output. In this talk, a direct-to-digital readout architecture for a CMOS Hall-effect sensor will be presented. It consists of a continuous-time sigma-delta ADC, whose input is directly connected to the output of a spinning-current Hall-effect sensor. Spinning ripple is removed by digital ripple-reduction loops, while switching spikes are mitigated by a novel “nano-timing” switching scheme. The resulting sensor achieves both low offset (16μT) and wide dynamic range (230mT).

Micro-electromechanical systems (MEMS) vibrating gyroscopes have been extensively utilized over the last two decades for automotive, industrial and consumer applications. Thanks to their continuous improvements in terms of lower cost, lower power consumption and improved short- and long-term stability, they are being continually used in established as well as emerging applications, such as advanced driver-assistance systems (ADAS) and virtual reality (VR). In this talk, the wide spectrum of readout interface architectures for integrated MEMS gyroscopes is reviewed. It starts with comparing conventional mode-matched closed-loop and split-mode open-loop readout systems. Next, a benchmark for advanced readout architectures ranging from full analog to the digital-intensive approaches is presented. During the talk, various system design specifications tradeoffs, such as area utilization, energy efficiency, zero-rate offset (ZRO) and vibration robustness (VRE), are highlighted. Finally, future trends in improving gyroscope performance driven by emerging applications are discussed.

Although robot’s can now communicate in many languages, they still can’t open a door – a phenomenon known as Moravec’s paradox. This is partly due to a lack of suitable tactile sensors and partly to an over reliance on vision sensors. In this talk, we present an integrated magnetic tactile sensor capable of measuring 3D forces. The sensor consists of a permanent magnet embedded in a deformable elastomer, which is mounted on top of a magnetometer chip. The chip incorporates multiple Hall-based magnetic transducers, a readout chain, on-chip thermal drift signal corrections, and a serial interface. The overall sensor enables robust differential 3D force sensing within a compact footprint (5 mm × 4.4 mm × 4.6 mm), and can resolve 10 mN (1 gram) in a 1-ms refresh period. The presentation will conclude with some examples of sensor deployment in robotic applications: intention detection in a wearable cuff for rehabilitation and dexterous manipulation with a robotic hand.

The increasing electrification of today’s world results in a widespread need to accurately measure large currents that are often at high voltages while reducing form factor, overhead power requirements, and cost. To that end, many applications today utilize magnetic-based current sensing which has the advantages of being inherently electrically isolated from the conductor and out of the current conduction path. However, magnetic-based current sensing has significant challenges. Among these sensitivity to unwanted magnetic fields which could be present from neighboring currents. This presentation will review several common techniques ranging from closed loop, magnetic core based solutions to open loop coreless solutions. While closed loop methods with compensation coils and magnetic cores provide excellent accuracy and bandwidth, there is a need for smaller and lower cost solutions for many of today’s current and emerging applications.  This is driving a need for simpler solutions with improved accuracy, which often require no magnetic cores or compensation coils and are therefore open loop. The focus of this presentation is the advantages and challenges of coreless and open loop solutions.

Bosch Quantum Sensing has been at the forefront of advancing the development and commercialization of NV quantum sensors, leveraging their unique quantum properties to enable exceptionally precise magnetic field measurements. NV technology offers numerous advantages over conventional sensors, including high sensitivity and the ability to operate under ambient conditions. Bosch is taking the next step in transforming quantum sensor research into portable sensor solutions. This endeavor necessitates the integration of complex multi-physical sensor arrangements into miniaturized devices, paving the way for exciting new applications, from detecting minute signals in medical diagnosis to enhancing airplane navigation.