Currently I am developing a led dimmer and am sorta at cross roads on which route to take for the output staging. The dimmer works using PWM (dc).
Basically I want to build a 6 channel LED dimmer that can dim something like 2A per channel @ 12/24v.
I say 12/24v because many of the commercial modules that are hitting the market these days tend to want to work off one these voltages, however others do exist. So I was hoping I could design the dimmer so that it could switch which output voltage it was opperating at.
Some other design overheads include:
- Overload protection
- Small board space
At the moment it looks like I have 2 options for handling the output stage:
1. Use discrete transistors
2. Use opamps
I had the opamp idea the other day after reading an article on using a opamp as a variable voltage powersupply. It seemed ideal in that they often come with overload protection, and changing the output voltage is just a matter of changing the feedback. Since board space is at a premium I also think perhaps using opamps could save some space.
Since I really am not all that familiar with opamps I thought i may as well post here and hope for some feedback.
Is my idea of using an opamp ok? or should I be looking at just using transistors?
If you could suggest any good links too that would be appreciated. (I have googled already but i'm probably looking in the wrong places)
Look foward to some replys.
Thanks in advance,