General description

The UBA20270 is a high-voltage power IC intended to control higher powered self ballasted Compact Fluorescent Lamp (CFL) lighting applications. The UBA20270 is a controller circuit with advanced features for dimming and has a lamp current controlled boost feature for boosting cold (amalgam) CFLs.

Features and benefits

2.1 Half-bridge features

■ Integrated high-voltage level-shift function with integrated bootstrap diode

2.2 Preheat and ignition features

■ Coil saturation protection during ignition

■ Adjustable preheat time

■ Adjustable preheat current

■ Ignition lamp current detection

2.3 Lamp boost features

■ Adjustable boost timing

■ Fixed boost current ratio of 1.5

■ Gradually boost to burn transition timing

2.4 Dim features

■ Continuously variable dimming function for standard phase cut dimmers

■ Natural dimming curve by logarithmic correction

■ Adjustable Minimum Dimming Level (MDL)

■ Controlled lamp ON/OFF

2.5 Protection

■ OverCurrent Protection (OCP) in boost and burn state

■ Capacitive Mode Protection (CMP)

■ OverPower Protection (OPP)

■ Power-down function

■ OverTemperature Protection (OTP)

2.6 Other features

■ Current controlled operating in boost and burn state

■ External power-down function

■ Lamp flicker suppression

Applications

■ Dimmable compact fluorescent lamps for power levels above 20 W and for universal mains voltages.