convert ir led signal to ir bus signal


New Member
i've been searching around looking for a diy solution to convert the ~5v LED output from my usb-uirt (similar to an ocelot) into a ~12v signal to input into my xantech ir distribution contoller. i've seen many references to the IRLINC 8175 from smarthome, but i haven't been able to find any circuit diagrams or examples to build one.

i've read that adding a diode in series with the 5v output signal from the usb-uirt will protect the 12v signal from the xantech from backfeeding back into the usb-uirt output circuit. the 5v output might be enough to pipe through the xantech controller. actually i know that the 5v signal is strong enough, i've hooked them up and verified (just not with the diode)...

i would prefer to do this by what i think is the correct way by using an opto-coupler circuit. i just don't know if the conversion from the 5v to the 12v system is just a straight amplification issue, or if there are other changes to the amplitude, freq., or carrier of the signal....

from what i've seen this a fairly common issue when using both HA/HTPC with IR distribution systems. if anyone could post a quick diy circuit, i'm sure it would help a lot of people. thanks!
thanks for quick replies! last night i got it working by placing a diode between the usb-uirt output and the xantech input. it's probably luck that the 5v output from the uirt is able to drive the 12v xantech, but it's working great now.

that two transistor circuit is slick, i booked marked it for later use. thanks!