将频率(或脉冲个数)转换成相应的直流电压(模拟量),在现代测量技术中是经常用到的。本文所介绍的是用一只PMOS集成片和一只运算放大器所组成的f—V转换电路,在实际使用中得到了满意的效果。这种电路的特点是结构简单、调试方便,可以直接带动电磁仪表进行显示,也可以同时带动函数记录仪进行记录,其原理方框图如图1所示。首先将输入脉冲(也可以是连续波)进行整形,使其变成一系列矩形脉冲,由于这些脉 Converting the frequency (or the number of pulses) into the corresponding DC voltage (analogue) is commonly used in modern measurement techniques. This article describes the use of a PMOS chip and an op-amp consisting of f-V conversion circuit, in actual use has been satisfactory results. This circuit is characterized by simple structure, easy debugging, you can directly drive the electromagnetic meter to display, you can also drive the function recorder to record the principle block diagram shown in Figure 1. First, the input pulse (which can also be a continuous wave) is shaped so that it becomes a series of rectangular pulses, due to these pulses