Charles A Couche

US Patent:

49879022, Jan 29, 1991

Filed:

Dec 30, 1988

Appl. No.:

7/292496

Inventors:

Charles A. Couche - Seattle WA

Assignee:

Physio-Control Corporation - Redmond WA

International Classification:

A61B 504

US Classification:

128696

Abstract:

An apparatus (10) for transmitting a patient physiological signal is provided. A converter (12) includes a front end circuit (28) that receives and conditions a patient physiological signal, V. sub. P, and produces conditioned signal, V. sub. C. A magnitude of V. sub. C is proportional to an amplitude of V. sub. P offset by a negative DC voltage. A track and ramp circuit (30) receives V. sub. C and produces a tracking voltage, V. sub. T. A magnitude of V. sub. T is inversely proportional to the magnitude of V. sub. C when the track and ramp circuit is in a tracking mode. A controller (16) includes a clock that produces clock pulses, V. sub. CK and a divider (38) that divides the clock pulse frequency and produces a trigger pulse, V. sub. TRIG. A leading edge of the V. sub. TRIG pulse starts a counter (40) counting V. sub. CK pulses.

US Patent:

51726912, Dec 22, 1992

Filed:

Jan 11, 1991

Appl. No.:

7/640056

Inventors:

Loren W. Gahnberg - Mill Creek WA
Charles A. Couche - Seattle WA
Peter Y. Choi - Seattle WA
Christopher Pearce - Monroe WA

Assignee:

Physio-Control Corporation - Redmond WA

International Classification:

A61N 1362

US Classification:

128419PG

Abstract:

A pacemaker/monitor (10) is disclosed for applying a pacing current to a patient through a pair of pacing electrodes (12). The pacemaker/monitor includes a plurality of manual inputs (26) for use by an operator and a microprocessor (16) that responds to programmed instructions stored in read-only memory (20). Cooperatively, these components control the operation of the pacemaker/monitor. In that regard, the desired magnitude of the pacing current in input to the pacemaker/monitor via a limitless rotary current control (46), formed by a rotary pulse generator (52) and a decoder circuit (50). The microprocessor monitors the operation of the various manual inputs and sets the pacing current to zero milliamperes in the event one of the inputs is used, regardless of the position of the rotary pulse generator. For example, when the pacemaker/monitor is turned ON, or the pacing mode of operation is selected, the pacing current is zeroed. Subsequent adjustments in the pacing current are then governed by the microprocessor in response to rotation of the rotary pulse generator.