John, can you jack up reference pin with a diode instead ? This will give you an o/p V of 5V+diode and allow you to use a 9V battery as the i/p limit has also been raised by a diode V This is something I do with zeners (k to pin, a to 0V) or trimpot to raise o/p to non-standard voltages. With a zener you need to have a couple of mA back from the o/p to the cathode to stabilise it, but I "think" you can insert a signal diode (eg 1N4148) in the reference pin path to ground, with cathode to 0V and anode to pin without needing any feedback as above. This would give you an o/p voltage of ~ 5.6V and an i/p range up to 9.6V _______________________________________________ http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist