| 摘要 |
<p>A pacemaker is provided having an improved circuit for obtaining a measure of battery end-of-life. The EOL detector includes an input stage with a current mirror output providing a current which is proportional to the current being consumed by the pacemaker circuitry, and thus being expended by the battery. The proportional current is directed to charge a capacitor, which is periodically discharged at a constant current, following which the battery goes through repeated cycles of charging and discharging. A measuring circuit measures the time of capacitor discharge, thereby providing a measure of battery energy discharge during the interval that the capacitor was charging. The interval counts are accumulated to provide an overall count representative of battery expenditure, and thus of pacemaker EOL. <IMAGE></p> |
