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:
Aug. 15, 2000
Filed:
Jan. 28, 1999
Kent W Leyde, Redmond, WA (US);
Heartstream, Inc., Seattle, WA (US);
Abstract
A defibrillator circuit that delivers high voltage electrical pulses and lower energy pacing pulses to a patient. The circuit allows the patient to be isolated so that no current leaks prior to the administration of the pacing or defibrillation pulse. In one embodiment, the delivery circuit includes a high voltage capacitor, with a GTO selectively connecting the positive terminal of the capacitor to ground. The negative terminal of the capacitor is coupled to one terminal of a bridge circuit, and another terminal of the bridge circuit is connected to ground. The bridge circuit has four SCRs which are selectively switched to produce the biphasic steering of current. Current conduction through the bridge circuit is initiated and commutated by the GTO. Turning on the GTO connects the positive terminal of the charged capacitor to ground, thereby lowering the potential of the negative terminal and causing current flow through the bridge circuit. By avoiding application of the capacitor voltage to the bridge circuit prior to energy discharge there through, a number of advantages are achieved over conventional defibrillator circuit designs.