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:
Mar. 03, 2020
Filed:
Jan. 18, 2019
Cirrus Logic International Semiconductor Ltd., Edinburgh, GB;
Terence Orr, Edinburgh, GB;
Cirrus Logic, Inc., Austin, TX (US);
Abstract
This application relates to amplifier circuits for amplifying an audio signal. An amplifier circuit () has a voltage regulator () for outputting a supply voltage to an amplifier (). An output capacitor () coupled to an output node of the voltage regulator. The voltage regulator is operable in a voltage-control mode to maintain the output voltage (V) at a nominal output voltage and in current-control mode to limit the input current drawn to exceed a defined limit. A controller () is operable in a first mode to define the nominal output voltage so as not to exceed a first voltage magnitude and in a second mode to define the nominal output voltage to be equal to a second, higher, voltage magnitude. The controller () monitors the audio signal for a high-amplitude part of the audio signal, that could result in the voltage regulator operating in the current-control mode to apply current limiting and, on such detection swaps from the first to the second mode until such a high-amplitude part of the audio signal has been amplified. The second voltage magnitude is greater than required for voltage headroom for amplifying the high-amplitude part of the audio signal so as to allow for a voltage droop of the output voltage over a plurality of switching cycles of the voltage regulator when operating in the current-control mode.