本文介绍一种绝对值放大电路,该电路只用一个运算放大器F007便可完成取绝对值和放大的功能.电路如下图所示. 当V_4>0时,D_1导通,D_2截止, V_b=(2KV_i)/(2K+1)-V_(be) 式中V_(be)为微小电流下(运算放大器偏置电流)的二极管正向压降.忽略失调电压和失调电流的影响,考虑到运放的增益很高,则 This article describes an absolute value of the amplifier circuit, the circuit using only one operational amplifier F007 can be completed to take the absolute value and amplification of the circuit as shown below.When V_4> 0, D_1 is turned on, D_2 ends, V_b = ( 2KV_i) / (2K + 1) -V be where Vbe is the diode forward voltage drop at a very small current (op amp bias current), ignoring the effects of offset voltage and offset current, The gain is high, then