Improved photoelectric isolator linear circuit

Published:2011/4/29 4:50:00 Author:Nicole | Keyword: photoelectric isolator | From:SeekIC

Using negative feedback technology can improve the transport linearity of photoelectric isolator device. In figure (a), when D1 is in the feedback path, its current is linear with V1. The shortage of this circuit is not considering the nonlinear relationship between photoelectric isolator device current current transfer ratio and working current. So we should choose and adjust devicecarefully. In figure (b), increasing secondary feedback can improve the linearity. The circuit gain is 1, the frequency is 0~30kHz, the dynamic range is -8~+8V, the nonlinear distortion(it is ±8V)is lower than 0.5%, the noise is lower than 1mV, the common-mode voltage is higher than 250V.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Basic_Circuit/Improved_photoelectric_isolator_linear_circuit.html

Print this Page | Comments | Reading(3)