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. 30, 2004
Filed:
Jul. 25, 2002
Applicant:
Inventors:
Assignee:
Other;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02P 3/14 ; H02H 7/09 ;
U.S. Cl.
CPC ...
H02P 3/14 ; H02H 7/09 ;
Abstract
In the invention, pairs of output transistors are provided. An actuator having an inductance is connected to nodes formed between the pairs of output transistors. A drive circuit for the actuator is arranged such that the actuator is driven by causing a drive current to flow into the inductance. The drive circuit has an overvoltage detection circuit for detecting whether or not a voltage appearing at the nodes of the output transistor pairs exceeds a supply voltage by a first predetermined level and whether or not the voltage becomes lower than a ground level by a second predetermined level. Output transistors connected to the nodes are activated by an output from the overvoltage detection circuit.