Primary-side regulator IC controls LED lighting accurately

Primary-side regulator IC controls LED lighting accurately

The HVLED805 LED lamp driver is claimed to enable designers to deliver more reliable and efficient LED retrofit lamps by featuring primary-side current regulation (PSR). The part integrates an 800-V avalanche-rugged MOSFET — achieved using the company’s high-voltage integration process — which is claimed higher than in competing devices and offers greater reliability, while further allowing a reduction in the snubber network as well. In addition, a high-voltage on-chip startup circuitry allows the device to start reliably when the ac line voltage is applied to the lamp.

PSR maintains the constant LED current that is needed to ensure consistent light output, without requiring the current-sensing components and optocoupler used in conventional secondary-side regulation. The elimination of these components decreases the cost and size of the LED driving circuitry and saves current-sensing losses, improving overall efficiency. By this, the device guarantees LED current regulation to within 5% accuracy.

Reliability is also enhanced, due to the elimination of the optocoupler in the secondary side, whose degradation can significantly decrease the mean-time-between-failure of the lamp. The highly efficient quasiresonant operating mode further boosts energy savings for LED lighting and dramatically reduces the EMI filtering required, saving space and costs. The chip is housed in a SO-16N narrow package. ($0.70 ea/10,000 — prod qty available now.)

By Christina Nickolas

STMicroelectronics , Lexington , MA
Information 781-861-2650
www.st.com