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:
May. 30, 2000
Filed:
Jul. 20, 1998
Dima David Shulman, Ocean, NJ (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
In a class AB amplifier circuit for use in an integrated circuit (IC) device, a bias circuit is used to bias a first field effect transistor (FET) in an output stage. A second FET in the bias circuit is connected to the first FET. The drain current of the first FET contributes to the output of the amplifier circuit. In response to a difference in inputs to the amplifier circuit in a transient state, the second FET operates in a non-saturation mode especially when the voltage of the power supply to the amplifier circuit is required to be low, e.g., 2 volts. As a result, an input voltage to the first FET which operates in a saturation mode increases, thereby increasing its drain current contributing to the amplifier circuit output. This increased drain current advantageously prevents the otherwise significant distortion in the amplifier circuit output during the transient state.