| 摘要 |
PURPOSE:To provide an inverter lighting device light-controllable in multistage without requiring adjustment. CONSTITUTION:An inverter lighting circuit with light control function is provided with, as a lighting control circuit 4, an oscillating circuit 3; a variable resistor VR; an A/D converter 7 for detecting the potential of the output end of the variable resistor VR and outputting corresponding reversed values of first and second load signals; a polarity reversing circuit 12 for receiving the reversed values and outputting the first and second load signals; a lower counter 9 for outputting the first load signal to a comparator 11 and outputting a carry signal; an upper counter 11 for outputting the second load signal to the comparator 11 and outputting the top column as a lighting control signal; and the comparator 11 for comparing the count values of the counters 9, 10 with a standard value and outputting a reset signal to the counters 9, 10 when both values are equal to each other to reset these count values. A switching element is controlled by this lighting control signal, and a DC power is switched to light a fluorescent lamp. |
