The rapid growth in portable electronics has driven the market for ultra low dropout regulators (LDOs) that are more power efficient and lead to longer battery lifetime. Over the years various topologies based on P- or N-channel pass transistors have been introduced to meet these demands. For each of these implementations, the LDO has had a significant disadvantage whether it is stability issues and lower current drive associated with Pchannel devices or the need for a charge pump to overcome the threshold voltage drop for enhancement mode N-channel devices. This paper presents a design methodology for an LDO that features a depletion-mode N-MESFET as the pass device that combines the advantages of both P and N devices allowing for ultra low dropout voltage and minimum layout area. The LDO also saves board space and simplifies design by achieving stability across all load and temperature conditions without the need of an output capacitor.

Original languageEnglish (US)
Title of host publicationMidwest Symposium on Circuits and Systems
Number of pages4
Publication statusPublished - 2009
Event2009 52nd IEEE International Midwest Symposium on Circuits and Systems, MWSCAS '09 - Cancun, Mexico
Duration: Aug 2 2009Aug 5 2009


Other2009 52nd IEEE International Midwest Symposium on Circuits and Systems, MWSCAS '09



  • Fully-depleted
  • Partially-depleted
  • Silicon-on-insulator
  • Silicon-on-saphire

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Electronic, Optical and Magnetic Materials

Cite this

Lepkowski, W., Wilk, S. J., Kim, S., Bakkaloglu, B., & Thornton, T. (2009). A capacitor-free LDO using a FD Si-MESFET pass transistor. In Midwest Symposium on Circuits and Systems (pp. 953-956). [5235924] https://doi.org/10.1109/MWSCAS.2009.5235924