High Accuracy Constant Current Circuit

Published:2011/8/23 23:40:00 Author:Robert | Keyword: High, Accuracy, Constant, Current | From:SeekIC

The picture shows the high accuracy constant current circuit and its practical application example. In the circuit shown in picture (a), it adds the grounding loop circuit between the constant current circuit and the load. Thus the current would return to be stable rapidly when the load has changed. The A1 and VT1 make up the voltage/current conversion circuit which could convert the ground voltage signal to the +15V voltage signal needed by the constant current circuit. The A2, VT2, VT3 etc. make up the standard constant current circuit. By setting R1=R2 it could provides the equal current I1=I2. VT5's base electrode is provided the +5V stable voltage by the zener diode VS1. So the VT5's emitter electrode voltage would keep +5.7V which would not be affected by the load changing.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Amplifier_Circuit/Other_circuit/High_Accuracy_Constant_Current_Circuit.html

Print this Page | Comments | Reading(3)