One-chip solution in 0.35 /spl mu/m standard CMOS for electronic ballasts for fluorescent lamps

An ASIC for full digital control of electronic ballasts for fluorescent lamps is presented. The one-chip solution is the functional integration of 3 chips, an IC for the PFC, a lamp management ASIC and a half bridge driver IC. The ASIC has 3 V compatible high precision ADC and comparator inputs, a fully digital controlled PFC, a digital regulation of the lamp power and a state machine establishing the lamp management. The outputs are 13 V high speed FET drivers that are directly controlled by the digital logic. The paper presents the topology of the electronic ballast, the interfaces to the two main control loops, and the main analog and digital blocks. The ASIC is fabricated in a 0.35 /spl mu/m standard CMOS process. The system building blocks and the topology can be used for various highly integrated power electronics applications.