L6585D

Combo IC for PFC and Ballast Control

The L6585D is a new and very useful choice for electronic ballast designs. The semiconductor embeds a PFC controller, a halfbridge controller, drivers and the logic necessary to build an electronic ballast. Offering programmability of the end-of-life windows comparator threshold, the L6585D is compliant with either ”lamp-to-ground“ or ”block capacitor-to-ground” configurations.

An outstanding feature is the L6585D’s ability to control and limit the lamp voltage during the ignition phase. The duration of the pre-heating and ignition phases can be set independently as can be the half-bridge switching frequencies for each operating phase (preheating, ignition and normal mode). Half-bridge overcurrent with frequency increase and PFC overvoltage features of L6585D allow for reliable and flexible solutions with a reduced part count. The PFC section achieves currentmode control operating in transition mode. The PFC output voltage is controlled by means of a voltage-mode error amplifier and a precise internal voltage reference. The PFC driver delivers 300 mA (source) and 600 mA (sink) and the drivers of the half-bridge supply 290 mA source and 480 mA sink. This combo IC for lighting applications packs into one small package all the functions required for correct operation of the ballast and prolonged lamp life.

Key Features

Independently programmable pre-heating and ignition phases
Ignition voltage control
Programmable and precise endof- life protection compliant with all ballast configurations
Transition-mode PFC with overcurrent protection
Auto-adjusting half-bridge overcurrent control
Automatic re-lamp
3 % oscillator precision
1.2 ìs dead time
PFC overvoltage protection and feedback disconnection
Undervoltage lock-out