Requirements for modern fluorescent lamp electronic ballasts focus on driver efficiency and safety aspects.
Previous dedicated ICs for ballast applications allowed designers to achieve good driver efficiency, but they required a lot of external circuitry to obtain good power factor correction, low THD and a full set of protection features.
The STEVAL-ILB005V2 demonstration board is based on the new L6585DE combo IC for ballast applications, which offers designers a highperformance PFC stage, and a high capability, fully programmable, half-bridge high-voltage driver. The device is also equipped with a full set of protection features.
Designed in high-voltage BCD off-line technology, the L6585DE embeds a PFC controller, a halfbridge controller, the relevant drivers and all the logic circuitry necessary to build an electronic ballast.
Another important feature of the IC is its capability to control and limit the lamp voltage during the ignition phase.
The pre-heating and ignition durations are independently configurable, as are the half-bridge switching frequencies for each operating phase (pre-heating, ignition and normal mode).
Other features, such as half-bridge over-current with frequency increase and PFC over-voltage, allow designers to build a reliable, flexible solution with a reduced component count.
- Maximum ignition voltage: 900 Vpk
- Lamp current (run mode): 455 mArms
- Preheating time: 1 s
- Maximum preheating voltage: < 240 Vac
- Ignition time: 60 - 100 ms
- Maximum THD: 8%
- Minimum PF required: 0.95
- Input voltage: 88 Vac - 277 Vac
- Output power: 54 W
- Input frequency: 50 Hz - 60 Hz
- Expected Input power: 60 W
- Lamp voltage (run mode): 110 Vrms
- Expected efficiency: 90%