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. 11, 1999
Filed:
May. 12, 1997
Paul C Gottshall, Washington, IL (US);
Long T Le, Peoria, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A low side driver circuit includes a command voltage source, a first switching transistor having a base connected to the command voltage source, an emitter connected to ground, and a collector connected to a second switching transistor base. The second switching transistor includes an emitter connected to a first reference voltage. A power transistor includes a gate connected to the second switching transistor collector through a first resistor, a drain connected to an electrical energy source through a load, and a source connected to ground through a sense resistor. A second resistor is connected between the power transistor gate and ground. A diagnostic circuit portion including a first comparator and a second comparator establishes a diagnostic output voltage based upon the voltages at the power transistor drain, gate and source for indicating fault conditions of the driver circuit.