驅動壓電式材料之多級放大電路架構研究

Abstract

本研究提出一多級式放大電路架構用以驅動壓電式負載，此放大器利用多級浮動訊號模組的疊加，產生一高電壓增益的輸出。文中首先介紹壓電式負載放大器電路的特性以及研究方法，隨後藉由多級式放大電路架構的分析及模擬，來探討此電路模型的可行性。此多級式放大電路系統，各級供應相同的輸出電壓以及電流，系統總功率消耗平均分配至各級電路當中，以致於多級式放大電路擁有高功率輸出的特點。文中提出一由六級浮動訊號模組所組成的電路原型，用以實現高輸入頻率以及不同電容式負載下的精密線性操作。其頻寬約為100 KHz、並可在400V的輸出擺幅下驅動0.1μF 的電容式負載；電路的迴轉率(Slew Rate) 高達115 V/μs，最大輸出電流為□2.6 A。

This study proposes a multi-level amplifier with connecting floating signal modules in series to drive piezoelectric devices. The amplifier generates a high voltage gain by summing the individual module gains. In the first instance this literature introduces the characteristic and various researching methods of driving piezoelectric loadings. Then the feasibility of multi-level amplifier topology will be discussed by simulations and analyses. Multi-level amplifier provides a means of achieving high power, and can divide the total power dissipation among the modules, because each module delivers the same output voltage and current. A prototype circuit that consists of six floating signal modules exhibits precise linear operation over a wide range of input frequencies and capacitive loads. The circuit provides a 400V output swing with a corner frequency of around 100 kHz at a driving capacitive load of 0.1 μF. The slew rate is as high as 115 V/μs and the maximum output current is □2.6 A.