EDIT: Post 74 has a very much updated board for those that are looking for the latest info on the board, however there is a lot of good discussion in between that is worth reading about the revisions.
Acknowledgments: Before I go any further, I want to acknowledge the work of Walt Jung. Many portions of the regulator are based on publications of his on his website and without it, this wouldn't exist. It also wouldn't exist without the work of Tangent and the publications of his on his website.
For some reason, the two things that keeping seeming to capture my attention are DACs and regulators. Don't know why, but they do. Over the last year and a half, I've sim'ed many different variety of regulators as just an interest kind of thing. During that time Tangent, for reasons that he has decided to keep private and I'm not going to pry, has decided to stop selling his regulators. I've also seen during that time a few people lament the fact that the TREAD is no longer available.
Well, I've decided to take a shot at building something TREAD sized. For lack of a better name it is called the r1. Unlike the TREAD, which is a LM317 based regulator, I figured a could build a Jung style regulator on the same size board. The size of the tread was 5cm by 3cm. My design, at the moment is 5cm by 3.3cm.
The basis of the regulator is taken from Walt Jung's 1997 article Regulator Excels In Noise and Line Rejection. With a few changes based upon other Walt Jung articles on constant current sources and buffered voltages references, the schematic was born:
My board layout at current (green top traces, red bottom traces):
At this moment, I looking for comments either on the schematic or the layout before I send it out for prototypes. I'm hoping that the layout should be fairly low noise.
I will post a few more comments on the layout soon, but being at work there is only so much I can post right now.
Edited by cobaltmute - 3/16/11 at 4:59pm