The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 21, 2017
Filed:
May. 15, 2013
Texas Instruments Incorporated, Dallas, TX (US);
Jianbao Wang, Tucson, AZ (US);
TEXAS INSTRUMENTS INCORPORATED, Dallas, TX (US);
Abstract
Power-supply ripple rejection (PSRR) at high frequencies is improved for an LDO voltage regulator with an NMOS pass transistor (MN). A ripple voltage (V) present on the input voltage causes a ripple current (I) through parasitic gate-drain capacitance of the pass transistor. A small ripple current (I) proportional to the ripple current (I) is generated and amplified to generate a cancellation current (I). The cancellation current is drawn from the gate of NMOS pass transistor (MN) to cancel the ripple current so that no net ripple current flows through the finite output impedance of an error amplifier (), to thereby achieve the PSRR improvement.