| 摘要 |
<p>A self-oscillating power supply circuit for driving a discharge lamp, the circuit including: a self-resonating inverter comprising a first FET (Q1) and a second FET (Q2) which operate in anti-phase, the inverter, in use, providing drive voltage across a load coupled to the inverter, the load comprising an impedance (L1a) having a reactive component; a transformer (T1) for coupling the first FET (Q1) and second FET (Q2); a tank circuit (C1) for cancelling the reactive component of the impedance (L1a) of the load; a feedback coil (L1b) coupled to the magnetic field of the discharge lamp which, in use, samples a fraction of the radio frequency energy in the proximity of the lamp; phase correction means for providing the correct phase at the first FET gate and the second FET gate; and a dc bias means (R3, R4) for starting the oscillator.</p> |
