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:
Jun. 13, 2000
Filed:
Mar. 12, 1998
Timothy L Johnson, Erie, PA (US);
Silverio S Leandro, Cambridge Springs, PA (US);
Snap-Tite Technologies, Inc., Wilmington, DE (US);
Abstract
A power circuit for controlling the amount of power delivered to a solenoid coil is disclosed. A current mode pulse width modulation controller is employed to interrupt the flow of current through a power branch of the circuit. A rectifying bridge enables use of the power circuit with either AC or DC power sources. The power circuit includes a startup current source for initially energizing the pulse width modulation controller. Two feedback voltages, one representing the compensated current through the power branch of the circuit and one representing the output voltage of the power circuit are used by the pulse width modulation controller to output pulses of varying duration at constant frequency to a field effect transistor. The opening of the field effect transistor interrupts the flow of current in the power branch of the circuit.