Constant charge time of defibrillation capacitor
US5800461A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 13, 1995 |
| Grant date | Sep 1, 1998 |
| Priority date | — |
| Expiry date | Nov 13, 2015 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/3975
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A capacitor charging circuit for charging a defibrillation capacitor in a constant period of time regardless of battery voltage by employing a controlled duty cycle charging technique. The defibrillation capacitor is charged in a piecemeal manner through a transistor and flyback transformer circuit. The gate of the transistor is driven by a constant frequency pulse train inverter drive signal in which voltage is conveyed to the capacitors during one-half of the full cycle of the pulse train. The primary of the transformer is controlled by each pulse of the inverter drive signal so that the secondary of the transformer supplies current to the defibrillation capacitors during the off half cycle of the drive signal, the charge being built up in the defibrillation capacitors incrementally during the off half cycle of the inverter drive signal until the predetermined voltage is reached.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.