• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Which one is better? (with or without output transistor)

Not open for further replies.


New Member
Hi all,

I am interested in current output that will be in different stages from 0-1mA, 0-100uA and so on. which is being selected by Q6 through Q9.
The pot at the non inverting input varies the voltage and so that it effects the output of the opamp.
The voltages at the nodes a,b,c and out is same with BJT at output or without. Please suggest me which method is better and why?

I shall be very grateful to you




Well-Known Member
None is better. For the type of schematics you post, PNG format would be much better than JPG considering file size and losses of quality.

Is this circuit ment to be a step regulated current source?

If that's the case, I would done it otherwise. I would have used either a jfet or a darlington bjt in this manner:


Last edited:
Not open for further replies.

Latest threads

EE World Online Articles