Hybrid Pseudo-Resonant Switched-Capacitor Drive Circuits for Electrostatic Micro-mechanical Actuators

近几十年来，用于便携式消费、工业和医疗应用的各种低功耗、小尺寸电子设备的增长和扩散。在许多情况下，这些平台需要传感器和执行器的机电接口、机械化控制、机器人和人机界面。新型静电(电场驱动)微型机电致动器包括压电器件、硅MEMS和介电弹性体，在克服传统磁基电机严重的尺寸和重量限制方面显示出巨大的潜力。然而，这些技术需要相关电子接口的新设计范例，这些接口必须提供高驱动电压(通常为100‘S伏至低千伏)，同时从低电压(个位数电压范围)电源升压，并且必须在小尺寸(~1cm3)和重量(~1g)下保持高效。一个独特的考虑是，在大多数情况下，静电设备主要是电容式的。因此，关键挑战包括以极小的尺寸提供高压双向DC-DC转换，同时在HZ-KHZ范围内高效地提供(和恢复)驱动频率下的无功功率。应对这些挑战可能会对医疗和生物医疗设备、微流体、成像、光学和通信、超声波和触觉界面等不同行业产生影响。该项目将涉及探索、设计和集成用于静电微机械执行器的高效、高电压、毫米级驱动电子设备。一种新的混合伪谐振结构将串并联型开关电容(SC)转换器和基于低压双向电感的DC-DC转换器融合在一起。这种混合方法融合了纯SC和基于电感的拓扑的优点，同时提供了回收(循环)存储在执行器主体介质中的能量的能力。该方案的智能优点包括电路技术、控制和通信概念，这些概念可以提供显著的优势--与传统架构相比，扩展了电压转换范围，提供了稳定的调节，消除了设计折衷，并将总功耗降低了一个数量级以上。该项目将包括对体系结构细节的研究，包括对混合转换器各个部分的电流、电压和额定功率进行优化分割，以在总尺寸为100mm3、重量为100 mg的情况下实现性能最大化。将开发一种新的、高度可扩展的电平转换策略，以实现芯片-芯片系列堆叠，允许驱动电压远远超过半导体埋氧化物(盒)击穿限制。一个集成电路(IC)原型将设计为300V SOI CMOS工艺，以演示从1.7-4.2V电源到低千伏驱动电压的高电压操作、执行器能量回收和芯片堆叠。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Recent decades have seen the growth and proliferation of a variety of low-power, small-size electronic devices for portable consumer, industrial, and medical applications. In many cases these platforms desire electromechanical interfaces for sensors and actuators, mechanized control, robotics, and human-machine interfaces. New electrostatic (electric-field-driven) micro-electromechanical actuators including piezoelectric devices, silicon MEMs, and dielectric elastomers show significant potential to overcome the severe size and weight limitations of conventional magnetic-based electric motors. However, these technologies require new design paradigms for the associated electronic interfaces, which must provide high driving voltages (typically 100’s of volts to low kV) while boosting from low-voltage (single-digit volt range) supplies, and must remain efficient at small size (~1cm3) and weight (~1g). A unique consideration is that electrostatic devices present as dominantly capacitive in most scenarios. Therefore key challenges include providing high-voltage bidirectional DC-DC conversion at extremely small size, while efficiently delivering (and recovering) reactive power at drive frequencies in a Hz-kHz range. Addressing these challenges could have impacts in diverse industry sectors from medical and biomedical devices, microfluidics, imaging, optics and communications, ultrasound, and haptic tactile interfaces.This project will involve the exploration, design, and integration of efficient, high-voltage, mm-scale drive electronics for electrostatic micro-mechanical actuators. A new hybrid pseudo-resonant architecture will be developed that merges a reconfigurable series-parallel switched capacitor (SC) converter with a low-voltage bidirectional inductor-based DC-DC converter. The hybrid approach merges the advantages of pure SC and inductor-based topologies while providing capabilities to recover (recycle) energy stored in the actuator bulk dielectric. The intellectual merit of the proposal includes circuit techniques, control, and communication concepts that can provide significant advantages – extending the voltage conversion range, providing stable regulation, eliminating design tradeoffs, and reducing overall power loss by over an order of magnitude compared to conventional architectures. The project will include the study of architecture details including optimal segmentation of current, voltage, and power ratings of the respective portions of the hybrid converter to maximize performance at total size 100mm3 and weight 100mg. A new, highly-scalable, level-shifting strategy will be developed to enable chip-chip series stacking, allowing drive voltages well in excess of the semiconductor buried-oxide (BOX) breakdown limit. An integrated circuit (IC) prototype will be designed a 300V SOI CMOS process to demonstrate high-voltage operation, actuator energy recovery, and chip-chip stacking to low-kV drive voltages from 1.7-4.2 V supplies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.