NXP chip offers improved “user experience” with CFLs

EDN Europe, 21 Oct 2009

NXP Semiconductors’ UBA2028 is a high-voltage power IC that lamp manufacturers will incorporate into compact fluorescent lamps (CFLs), enabling them to produce CFLs with characteristics that rival some of the desirable features of incandescent bulbs, with quick warm-up and dimming down to 10% of full light intensity. IC features a high level of integration for compact designs, efficient power conversion, and extended CFL lifetimes beyond 15,000 hours.
NXP is designing CFL driver ICs, including the UBA2028, in anticipation of a shift toward higher-quality compact fluorescents. The UBA2028 introduces what NXP calls “true dimming” capabilities, free of flicker and noise. A high level of integration enables more compact CFL sizes that can fit smaller lighting product designs.
The UBA2028 is a 600 V power IC that can drive and control dimmable CFLs up to 21W, and features 3-Ω integrated switches. The IC includes a half-bridge power circuit, a dimming function, a high voltage level shift circuit, an oscillator function, a lamp voltage monitor, a current control function, a timer function, and detection and protection circuits. It supports steady-state currents up to 280 mA and ignition currents to 1.5A, with adjustable preheat time and current. It incorporates a range of features specific to the application of driving a CFL, including lamp failure detection; it comes in a SO20L package, which has a typical Rth(j-a) (thermal resistance, junction-to-ambient) of 75 K/W. An application kit supports initial designs.