Electronic Circuits and electronic circuits, electronic schematics plus an extensive resource for hobbyists, inventors and engineers

DiscoverCircuits.com, has 45,000+ electronic circuits, cross-referenced
into 500+ categories.    We have searched the web to help you find quick design ideas.
We make every effort to link to original material posted by the designer. 
Please let us if you would like us to link to or post your design.

HOME Schematics Index Hobby Corner Dave's Circuits Electronic Resources Contact Info
Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches


MOSFET LDO Voltage Regulator
All materials and content contained on this page are the exclusive intellectual property of Andrew R. Morris and
may not be copied, reproduced, distributed or displayed without his express written permission.

This circuit has excellent voltage regulation, due to positive feedback through R2 however the circuit must be started up.  This is done by Q4 and Q5.  If the circuit does not need to be started under load, Q4, Q5, and R6 can be deleted.  You must then place a 1 meg resistor between the source and drain of Q1.  C2 slightly speeds response to rapid load changes and can be changed in value or deleted.

Due to the extremely high impedances to this circuits, it would oscillate with capacitive loads on a protoboard, but with stable when built up on a small piece of perfboard.  The circuit draws an overhead current of less than 10uA.  Drop-out voltage approaches zero.  It is entirely dependent on the load and the Rds of Q1.  The only shortcoming of the circuit is that the set voltage will vary from one Q3 part to another.  Each copy of the circuit would have to be adjusted.

More:  MOSFET Circuits; Voltage Regulators Regulator Circuits
Click on Schematic to view PDF

Got Designs?
Please eMail
if you want me to link to and/or post your original design Thanks.


HOME Schematics Index Hobby Corner Dave's Circuits Electronic Resources Contact Info
Imagineering Ezine    Discover Solar Energy Dave Johnson & Associates Faraday Touch Switches


 About Us   |  Advertise on DiscoverCircuits.com   |   Report Broken Links  |    Link to DiscoverCircuits.com  |    Privacy Policy


Copyright  January, 1998 - November, 2017     David A. Johnson & Associates.  All Rights reserved. 


 Linking is ALLOWED but COPYING any content or graphics to your web site is EXPRESSLY PROHIBITED.