Design of the Numerical Current Source with High Precision
Run Liu · Modern Electronics Technique · 2006
Constant current control is realized by a closed loop negative feedback,which is composed of hardware circuits.In order to improve the current accurately,two 8 b D/As are adopted to form a 16 b D/A circuit.The single chip microcomputer 89C52 is mainly used for controlling D/A circuit to produce stable control voltage and controlling A/D circuit to measure the current.Meanwhile,it also manages the manmachine interfaces such as the keyboard and display.Tests show the aims of high precision,fast response,excellent stability and wide output rang are finally achieved.