| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a lighting device and lighting equipment that can suppress part failure even when coil current cannot be detected.SOLUTION: A lighting device 10 has a rectifying circuit 6 which is connected to an AC power source 4 and is typically a diode bridge for rectifying an AC voltage, a capacitor C1 connected to the output terminal of the rectifying circuit 6 in parallel, a voltage dividing circuit of resistors R1, R2 connected to the capacitor C1 in parallel, and an H bridge circuit 14 for receiving DC current which is subjected to full-wave rectification in the rectifying circuit 6. A microcomputer 22 fixes a frequency f just after power-up, and generates a switching signal Q2/SW whose ON time width ton is fixed, thereby surely turning on/off the switching element Q2. Thereafter, by generating the switching signal Q2/SW, the microcomputer 22 switches the control to so-called bang-bang control under which the coil current IL reciprocatively increases and decreases between an upper limit current value IL*max and a lower limit current value IL*low.</p> |
