Editor's note: STMicroelectronics has introduced a single-chip fluorescent electronic ballast IC (Combo IC) that integrates a power factor corrector (PFC) with a half-bridge controller in one chip and all related Drives and logic circuits. By integrating these functions on a single chip, ST's new device, the L6585, increases the brightness of the lamp while reducing power consumption and complying with relevant electrical safety and power consumption regulations. According to reports, the L6585 is the first single-chip solution on the market to achieve EOL (end of lamp life) detection in the "light to ground" or "blocking capacitor to ground" configuration of the ballast. For the first time, ballast manufacturers can choose how to design target applications to simplify board inspection and smooth ballast safety detection. The previous solution to achieve EOL detection and the special safety features of the new fluorescent lamp required a Combo IC and several external components, and the new product L6585 can provide all these necessary functions through one chip, eliminating the need for any external circuitry. The shortening of the design cycle greatly reduces the design complexity and cost, and comprehensively improves the reliability of the product. The L6585 IC features independently programmable warm-up time and ignition time as well as half-bridge frequency for each stage of operation. Therefore, this single IC can be used for many different types of lamps. The Combo IC provides high security protection for both the PFC and the half bridge on the chip. In addition to limiting the voltage and current on the lamp during ignition and normal operation, the L6585's overcurrent protection prevents capacitor mode from appearing in the half-bridge section to further improve ballast reliability. According to STMicroelectronics, the L6585 has many other advantages. For example, the PFC overvoltage and feedback disconnect detection function can turn off the IC to prevent the ballast from being damaged. The high linear multiplier enables the ballast to operate at a wide voltage. At the same time, the total harmonic distortion (THD) is very low. The automatic replacement of the lamp function of the new device greatly simplifies the management of the lamp, and the electrician does not need to close other normal working lights when replacing the damaged lamp. The L6585 is available in a SO20 ECOPACK package and is priced at $1.40. Samples of the Combo IC are available now, with volume production scheduled for January 2007
1
1
INT Metal Products Factory , http://www.libometal.com