| 摘要 |
<p>In an electrosurgical generator having a self-tuning oscillator which includes a switching device (10) and a resonant output network (12) connected between the switching device (10) and a supply rail (V+), an oscillator feedback circuit (26, 28, 30, 32, 34, 38) feeds to the switching device (10) a switching control pulse signal for separately switching the switching device (10) to its 'on' state whilst the voltage across the device (10) is decreasing, the phase of the 'on' point being dynamically variable such that the 'on' time of the device (10) is adjusted so as to regulate the amplitude of the voltage thereacross. This allows reverse conduction of the switching device (10) to be avoided, giving improved efficiency.</p> |
