alan smith wrote: > Thinking a > NPN/PNP pair (2N3904/2n3906) inside the feedback loop might be the > easiest way? They are rated for 200mA continuous, so that would > provide the necessary drive. You need to look at a lot more than just the current rating of the transistor. Yes, that needs to be sufficient, but a 3904/3906 pair could easily be overstressed. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist