Hello, I am sorry for my poor English...also I am a newbie of electronic... I really want to make this project for my first and serious project.. I want to ask somting abt this project...hope anybody can answer me...thanks you. 1. Which precise part is control current and control voltage..??How to separate them?? 2. I would like to separate to make it. How can i separate the circuit and test for it?? 3. If I use 0-10 V DAC's Vref to repace P1 and P2 ...how can i change the circuit..? please draw the circuit for me...please.. 4. And how to caculate the change part if I use another Vref of DAC?? 5. Does any body have a right schematic??? coz i read the post know that the original schmeatic have some bug Thanks for answering