It could be possible to invert a logic signal using a transistor, however I recommend an alternate solution. Several companies, including TI, PERICOM, and TOSHIBA, now make a series of small package single gate parts. It is possible to find inverters, 2 input gates like AND, NAND, OR, NOR and XOR, buffers, and even a FF part.

Here is a link to the data sheet for one such part from Toshiba.

I have used these these types of parts many times and find them to be the perfect solution to the kind of issue you have right now.

Another place they can be very useful is to buffer a signal on a board that has wide fanout. On one design I did about 7 years ago I had a Mot microprocessor that outputted a clock signal to the system logic board. This signal had to buss to many connections and the processor just was not capable of driving the signal line with a nice square wave. So I inserted one of these buffers and the problem was solved. The use of the small package permitted the high frequency signal to be routed from the microprocesor to the buffer over less than 5 mm of trace length, thus eliminating ringing on the signal line.

Michael Karas