General description
The UBA20271/2 are high-voltage power ICs intended to drive and control higher powered self ballasted Compact Fluorescent Lamp (CFL) lighting applications. The UBA20271/2 operate from 120 V and 230 V. The module includes a half-bridge power circuit of two NMOST power FETs. In addition, a controller circuit is included that has advanced features for dimming and a lamp current controlled boost feature. The boost feature is used for boosting cold (amalgam) CFL.

FEATUREs and benefits
Half-bridge features
■ UBA20271: Two internal 350 V, 1.0 Ω, max 5.0 A NMOST half-bridge power FETs
■ UBA20272: Two internal 600 V, 3.0 Ω, max 2.7 A NMOST half-bridge power FETs
■ Integrated high-voltage level-shift function with integrated bootstrap diode

Preheat and ignition features
■ Coil saturation protection during ignition
■ Adjustable saturation protection level
■ Adjustable preheat time
■ Adjustable preheat current
■ Ignition lamp current detection

Lamp boost features
■ Adjustable boost timing
■ Fixed boost current ratio of 1.5
■ Gradually boost to burn transition timing

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

Protection
■ OverCurrent Protection (OCP) in boost and burn state
■ Capacitive Mode Protection (CMP)
■ OverPower Protection (OPP)
■ Power-down function
■ OverTemperature Protection (OTP)

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 from 5 W to 20 W directly operating from 230 V (UBA20272) and 120 V (UBA20271) mains voltage.