Optimum Design of a New High Voltage Cascaded Amplifier Based on OPA454

In order to obtain high linearity voltage signal with adjustable frequency, an optimal design scheme of high voltage cascaded linear amplifier based on OPA454 is proposed in this paper. Firstly, the main circuit, isolation circuit and cascade amplifier circuit of the high voltage cascade amplifier are designed. Then, the negative feedback characteristics and capacitive load characteristics of the linear amplifier are analyzed to ensure the high linearity and capacitive load capability of the output voltage signal. Finally, a two-stage cascade amplifier circuit model is built and tested in time domain at 0.001 Hz, 1.0 Hz and 1.0 kHz. The frequency response curves of the first-stage voltage amplifier circuit and the two-stage voltage amplifier circuit are compared in the frequency domain. The results show that the output voltage waveform of the new linear amplifier can be linearly amplified by 40n times of the input voltage, which achieves high linearity and low waveform distortion. It meets the requirement of accurate voltage amplification under adjustable frequency.