El Segundo, Calif. - International Rectifier's 600-volt IR21592 and IR21593 dimming ballast ICs, each with a phase control loop and half-bridge driver for fluorescent lamps, eliminate the need for a current-sensing transformer. IR says these new devices offer the most comprehensive set of sense and control features available, including ignition detection and full-scale dimming, as well as brownout- and over-temperature protection. A microcontroller interface is included for maximum flexibility in programming such parameters as preheat time and current, and ignition-to-dim time.
"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 meeting the requirements of so-called linear lamps while the IR21593 is designed for compact-style fluorescent lamps. A patented phase control loop architecture senses and regulates the phase current of the half-bridge. An external current-sensing resistor is used to measure all feedback information necessary for pre-heat, ignition, dimming, and to detect lamp fault. Key device specifications include a source/sink capability of 250/400 mA and a dimming range of 1 to 100 percent as set from a 0.5 to 5-volt input. The devices are available in a 16-lead DIP or SOIC.
Design tips, application notes, and other design support are posted on the company's web site at www.irf.com/product-info/lighting/fluorescent.html.
The IR21592 and IR21593 are priced at $1.50 each in 50k quantities. The devices are available immediately.