Our friends at AnalysIR who make Windows software to assist in decoding IR signals have come up with a nice schematic for a constant current IR LED driver circuit that we thought would be of interest to our users here. Here is a link to their blog post describing the circuit. We’ve not tested it out here yet but we have seen similar schematics and we trust these guys to do it right anyway. Their explanation of the circuit is outstanding.

They also have many other interesting articles in their blog and they have a user forum with lots of interesting information and exchange of ideas between users.