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. 16, 2002
Filed:
Mar. 30, 2001
Alaa Y. El-Sherif, Dallas, TX (US);
Joao Carlos Brito, Richardson, TX (US);
Marcus M. Martins, Richardson, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A circuit ( ) to provide drive voltages to a voice coil motor (VCM) ( ) of a hard disk drive ( ) has identical high and low side drivers ( and ) connected to the VCM ( ). Each driver has an output FET ( ) selectively connecting the VCM ( ) to a control voltage ( ). A Class-AB output pair ( and ) in parallel with the output FETs ( and ) provides continuous and linear Class-AB operation at the output node ( ) around the crossover point, while the output FETs ( and ) are kept not conducting. This approach offers extremely low level of crossover harmonic distortion. Each FET of the Class-AB pair ( and ) is connected to a biasing FET ( and ) to provide the desired Class-AB quiescent current. Preferably the output FET ( ), quiescent current controlling FET ( ), and biasing FET ( ) are fully integrated.