ZHU Wu, ZHANG Jia-min. Cancellation of nonlinear error of bridge using op amp feedback control[J]. Optics and precision engineering, 2007, 15(6): 910-914.
ZHU Wu, ZHANG Jia-min. Cancellation of nonlinear error of bridge using op amp feedback control[J]. Optics and precision engineering, 2007, 15(6): 910-914.DOI:
A method to reduce the nonlinear error of a bridge using operational amplifier (op amp) feedback were introduced
the feedback conditions of canceling nonlinearity were found by circuit analyzing. Ignoring input bias current and input noise voltage of op amp in four linearity circuits
the output expressions for affect of offset voltage on measuring system were given.The correction characteristic of each method was analyzed to attain optimal testing bridge circuit to reduce the errors of offset and drift by five times. The results show the method can provide a theory guidance for choosing op amp and determining method in bridge circuit measuring system.