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:
Dec. 21, 1999
Filed:
Dec. 10, 1998
Timothy A Harris, Calgary, CA;
Revolve Magnetic Bearing Inc., Calgary, CA;
Abstract
A method of controlling switching of a tri-state switching amplifier having two switching legs, two switches in each leg, and a load connected to the junction between the switches of each leg, a power supply and a capacitor connected to the opposite ends of each leg, a first pair of the switches defining an idle state in which current circulates through the load and the first pair of switches, a second pair of the switches defining a Charge state in which the load is connected to the power supply and current through the load increases and a third pair of switches defining a Discharge state in which the load is connected to the power supply and current through the load decreases, the method comprising generating a first PWM signal at the beginning of each pulse of a clock signal; generating a second PWM signal when a binary current error signal changes state; generating, at the beginning of each pulse of the clock signal, a Direction signal which is the inverse of the current error signal; and placing the amplifier in the idle state when the second PWM signal is present and otherwise placing the amplifier in the Charge state for one state of the Direction signal and placing the switches in the Discharge state for the other state of the Direction signal.