Patent ID: 6687543
Filing Date: 2004-02-03
Classification: A61N

Abstract:
A processor controlled implantable cardiac stimulation device having a processor, a real-time clock circuit, a watch dog timer circuit having a duty cycle, a telemetry circuit capable of operation in either an active mode or a standby mode, and ancillary circuits that sense cardiac activity and provide stimulation pulses to a heart, the device comprising:a power source for providing power to all of the circuits of the device; and a shelf mode circuit that disables power to the ancillary circuits, decreases the duty cycle of the watch dog timer, sets the processor into a static state, and sets the telemetry circuit to the standby mode in response to shelf mode commands received by the telemetry circuit to set the device from an active powered mode to a shelf mode and reduce shelf current consumed by the device; wherein the watch dog timer remains operational at a reduced rate to detect processor errors during the shelf mode; and wherein a transmitting circuit of the telemetry circuit is disabled during the shelf mode and a receiving circuit of the telemetry circuit remains active during the shelf mode.