Now it makes sense...using the feeback to force the regulation. Next question is...related to such a design, and the answer might be there are always a dozen ways to get to the end.... Is there any sort of advantage to using this type of design for voltage regulation over say a small LDO or other type of LinearTech or Maxim part that is designed for a voltage regulator? Maybe its cost...and thats an issue... _________________________________________________________________ MSN 8 helps eliminate e-mail viruses. Get 2 months FREE*. http://join.msn.com/?page=features/virus -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu