AVR-Chat

> I have looked over the
>datasheet ( http://www.dpicts.com/Laa110.pdf ) many times and can not
>find an input voltage anywhere.

There isn't one. They are just IRleds, so as long as you have 2-3 volts across them, you'll be fine.  

 From the spec, you may need anywhere from 5-50mA before the output turns fully on though. The AVR won't drive that directly, so you still need the switching transistor.  No diode though, since we now know for sure, that you don't have a coil involved.

You also need to make sure that the current through the LED is << 400uA in the "off" state. This is what I was talking about before, using a pulldown resistor on the AVR pin that drives the transistor. Otherwise, while the AVR is in reset, you have no output drive from the AVR, and the base diode of the transistor makes a nice RF detector to turn your relay on when you didn't expect it.

This device is like a conventional relay in one sense, it is activated by CURRENT through it, not voltage.