Have you looked at a single supply CMOS Rail-Rail op-amp? You could do the same thing but run it off the PIC supply. Try Maxim, Linear Technology, or National Semiconductor(Com Linear). - -Mark >>> Matt Ormsby 6 December 1996 10:24 am >>> I ran into a small problem with a circuit and was hoping for some help. I have an output from another device of which runs 1.1 volts on to 0 volts off. - -snip- - So I started thinking about a 741 op amp and played with that with success. This is the problem. I don't have room for a - supply on this board. Does anyone have a way that I can get this output up to a good ttl level with a meg ohm input resistance or so? Thank you for any and all help. Matthew Ormsby Matt@epfsc.com http://www.cyberport.com/~mormsby