论文部分内容阅读
设计了一种用于电分析仪器的高精区微电流测量电路。通过改进电路设计显著提高了电路的稳定性和响应速度。采用驱动屏蔽技术提高了信号输入端输入阻抗并消除其奇生电容。设计印刷电路板时，充分考虑电磁兼容性，优先选择性能优异的高速低噪声电子元器件。微电流测量部分进行独立屏蔽。通过这些手段可将电分析仪器的电流测量范围扩展到pA量级，电路噪声降至0．05pA。
A high precision micro-current measurement circuit is designed for electrical analysis equipment. By improving the circuit design significantly improves the stability and response speed of the circuit. Drive shield technology improves the input impedance of signal inputs and eliminates their odd-value capacitance. Design printed circuit board, give full consideration to electromagnetic compatibility, priority to choose high-performance low-noise electronic components. Micro-current measurement section for independent shielding. By these means, the current measurement range of the electro-analytical instrument can be extended to the pA level and the circuit noise can be reduced to 0.05 pA.