| 摘要 |
<p>A dimmable fluorescent lamp ballast comprises a filter and rectifier circuit (1) connected to a main power source, a stepped dimming sampling circuit, a linear and stepless dimming sampling circuit, and a dimming control circuit (7). The dimming control circuit (7) comprises a stepped dimming module (3), a linear and stepless dimming module (2), a switch (4) and a circuit controller (6), wherein the switch (4) is selectively connecting the stepped dimming module (3) or the linear and stepless dimming module (2) to the circuit controller (6) respectively. The present invention integrates both functions of stepped dimming and linear and stepless dimming into one fluorescent lamp ballast. According to the present invention, either the linear and stepless dimming of or the stepped dimming of the fluorescent lamp can be effected readily by a silicon controlled rectifier dimmer or a power switch when necessary.</p> |
