EL SEGUNDO, Calif. March 2004 - International Rectifier, IRŪ (NYSE: IRF), a world leader in power management technology, today announces the 600V IR21592 and IR21593 dimming ballast ICs, each featuring a phase control loop and half-bridge driver for fluorescent lamps. IR's new devices include the most comprehensive set of protection features including dimming ignition detection as well as brown-out and over-temperature protection. In addition, a micro-controllable interface is included.

"The IR21592 and IR21593 ICs simplify dimming fluorescent lamp architecture into a single-chip solution. They enable ballast manufacturers to offer solutions that save energy. Advancements like these should pave the way for more widespread adoption of the energy-efficient lighting alternative," said Leigh Cormie, Lighting Product Manager.

The IR21592 is designed for linear lamps while the IR21593 is designed for compact lamps. IR's patented phase control loop architecture senses and regulates the phase current of the half-bridge. Only a single pin with an external current-sensing resistor is used to measure all feedback information necessary for pre-heat, ignition, dimming and lamp fault. The result is a closed loop system that simplifies linear dimming. The control method eliminates a separate current-sensing transformer. Key specifications include:

Vcc Max	Isource/Isink	VCO Input Range	Dimming Range	Tj Range	Package
600V	250/400mA	0 to 5V	1% to 100%	-55 to 150C	16 lead DIP or SOIC

Design tips, application notes and other design support are posted on the International Rectifier Web site.Go to http://www.irf.com/product-info/lighting/fluorescent.html.

Availability and Pricing

Pricing for the IR21592 and IR21593 is US $1.50 each in 50,000-unit quantities. The devices are available immediately.