Published Paper Details:

This paper compares three distinct approaches to signal amplification and conditioning for piezoelectric sensors and light intensity measurement. The first approach addresses the challenge of amplifying weak charge signals from piezoelectric plates in shape detection, proposing a compact, high-integration charge amplifier circuit with strong anti-interference capabilities. This design, validated through Multisim simulations and actual tests, demonstrates good passband flatness and less than 2% theoretical error, highlighting its feasibility and reliability. The second approach presents a novel charge amplifier for piezoelectric sensors, particularly beneficial in quasi-static applications. By eliminating the need for extremely large resistors and utilizing a simple analog and linear feedback network with general-purpose JFET operational amplifiers, the proposed circuit significantly reduces output offset voltage and implementation costs. Experimental results show a low-cutoff frequency of 0.2 Hz and a gain of 20.5 dB, with a minimal output offset voltage and a relative error of 2.1%. The third approach evaluates different signal conditioning circuits for light intensity measurement using LDR and photodiode sensors. It emphasizes the importance of accurate light measurement for various applications and highlights the performance of instrumentation amplifiers for fixed lux ranges and active low-pass filters for variable lux ranges. This comparative analysis underscores the advancements in signal conditioning solutions tailored to specific applications, enhancing measurement accuracy and efficiency.