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This paper introduces a lean noise-cancelling sturdy-MASH delta-sigma ADC, achieved through the implementation of a noise-shaping SAR second stage, the use of which instead of the usual delta-sigma stage, eliminates, by virtue of its inherent feedforward mechanism, the quantization noise of the first stage. Moreover, any mismatch-induced error of the noise-shaping SAR gets shaped by the first stage, circumventing the need for strict capacitor matching or calibration. The elimination of noise-cancelling and/or calibration circuitry, as well as the inclusion of the area-efficient noise-shaping SAR qualify this topology as lean. Simulations demonstrate a proof-of-concept design achieving 107.7 dB SQNR for an OSR of 14 over a 1 MHz bandwidth.

This paper presents the design and simulation of a levitating MEMS speaker. The device is composed of a levitating membrane actuated through electrostatic forces using several electrodes and a control system. The absence of supporting anchors allows for a drastic reduction of damping losses and therefore promises higher power efficiency. Simulation results indicate very promising performance.

This paper proposes a system in package (SiP) for ultrasonic ranging composed of a 4 × 8 matrix of piezoelectric micromachined ultrasonic transducers (PMUT) and an interface integrated circuit (IC). The PMUT matrix is fabricated using the PiezoMUMPS process and the IC is implemented in the AMS 0.35 µm technology. Simulation results for the PMUT are compared to the measurement results, and an equivalent circuit has been derived to allow a better approximation of the load of the PMUT on the IC. The control circuit is composed of a high-voltage pulser to drive the PMUT for transmission and of a transimpedance amplifier to amplify the received echo. The working frequency of the system is 1.5 MHz.

This paper presents the design and simulation of a mass sensitive Lamb wave microsensor with CMOS technology provided by SilTerra. In this work, the effects of the metalization ratio variation on the transmission gain, total harmonic distortion (THD), and two different resonant modes (around 66 MHz and 86 MHz) are shown. It has been found that the metalization ratio can be adjusted in order to obtain a compromise between transmission gain and sensitivity, depending on the design criteria. By adding a Si3 N4 layer on top of the device, a five-fold improvement in transmission gain is reached. It was also shown that the transmission of the input differential IDT configuration is 20% more efficient than a single terminal. With this combination, the mass sensitivity is about 114 [cm2 /gr].

Micro-machined acoustic and ultrasonic transducer (MAUT), particularly piezoelectric MAUT (PMAUT), performance tradeoffs have meant reasonable pixel depth resolution necessitated low quality factor (Q) transducers with power distributed over a large bandwidth yielding modest imaging ranges whilst high-Q transducers providing higher acoustic power output for longer imaging ranges exhibit extended ringing limiting pixel depth information. Accordingly, the inventors have established MAUTs supporting high-Q transducers for long-range high-resolution imaging by integrating electromechanical actuators (dampers) which can be selectively engaged to mechanically damped the MAUT. In several applications PMAUT arrays are required where all transducer elements should have almost identical resonant frequencies. However, prior art fabrication processes have tended to produce PMAUTs with large inter-chip and inter-wafer variances. Prior art methodologies to reduce inter-wafer process variations do not address intra-wafer or inter-chip process variations and accordingly the inventors have established manufacturing methodologies and design solutions to address these for the PMAUT resonant frequency.

This work introduces a novel direct current electroosmosis (DCEO) micromixer designed for rapid and efficient fluid mixing. This micromixer demonstrates excellent capability, achieving approximately 98.5% mixing efficiency within a one-second timespan and 99.8% efficiency within two seconds, all within a simple channel of only 1000 µm in length. A distinctive feature of this micromixer is its ability to generate robust and stable helical vortices by applying a controlled DC electric field. Unlike complex, intricate microfluidic designs, this work proposes a simple yet effective approach to fluid mixing, making it a versatile tool suitable for various applications. In addition, through simple modifications to the driving signal configuration and channel geometry, the mixing efficiency can be further enhanced to 99.3% in one second.