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:
Apr. 01, 2003
Filed:
Mar. 19, 2002
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
The low dropout voltage regulator (LDO) circuit with improved power supply rejection ratio includes: a first amplifier having a first input coupled to a reference voltage node V ; a second amplifier having an input coupled to an output of the first amplifier ; a pass transistor having a control node coupled to an output of the second amplifier ; a feedback circuit and having an input coupled to the pass transistor and an output coupled to a second input of the first amplifier ; an inverting gain stage coupled to the input of the second amplifier ; and a high pass filter , and coupled between a power supply node and a control node of the inverting gain stage . The circuit uses the high pass filter , and and inverting gain stage to feedforward the power supply ripple into the LDO's control loop which counter-acts the impact of the supply ripple on the output node V .