| 摘要 |
<p>A circuit arrangement for an electrodeless fluorescent lamp having EMI suppression characteristics and which is effective for producing an RF signal to excite a fill contained within a lamp envelope portion (12) of the electrodeless lamp (10), includes a ballast circuit arrangement (24) receptive of line power and effective for converting the line power into the RF signal for driving the discharge (23) within the lamp envelope (12). The ballast circuit arrangement (24) includes an excitation coil (16) which extends within a re-entrant cavity (15) formed in the lamp envelope (12). A first tuning capacitor (26) is connected on one end to a first end of the excitation coil whereas a second tuning capacitor (27) is connected on one of its ends to the other end of the excitation coil (16), the capacitive values of the first and second tuning capacitors being substantially the same. The split capacitive arrangement is effective in cooperation with the excitation coil for producing the RF signal and does so in a manner to minimize EMI emissions that would otherwise be produced by an unbalanced load across the excitation coil.</p> |
