Controlled load regulation and improved response time of LDO with adaptive current distribution mechanism
US8471538B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 25, 2010 |
| Grant date | Jun 25, 2013 |
| Priority date | — |
| Expiry date | Aug 18, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F1/575
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A low drop-out (LDO) voltage regulation circuit includes first and second internal current paths. The first internal current path is between the input supply voltage and ground and includes the regulator's buffer circuit. The second internal current path is between the input supply voltage and ground and includes the regulator's power transistor. The amount of current flowing through the first internal current path relative to the amount of current flowing through the second internal current path is an increasing function of a current supplied to a load connected to the output supply node. The load regulation of the LDO is improved as the DC gain will not go down at lower load currents. Further, the no load to full load response time is improved as the load pole and power MOS gate pole are actively controlled with respect to output load current. In this mechanism, as the amount of current being supplied to the load decreases, the internal current flow shifts from the first internal current path to the second internal current path and vice versa. This arrangement maintains the desired pole structure and keeps the quiescent current largely the same for all load current levels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.