March 3, 2014, Seoul – A global semiconductor company contributing to customers across various electronic applications
STMicroelectronics (hereinafter ST), a company, has unveiled a complete and configurable solution for the development and efficient management of high-definition LED strings (up to 100W) capable of brightness adjustment for street lighting.

The plug-and-play street light design solution introduced this time is based on the STLUX385A digital power controller chip, which won an award at CES earlier this year, and fully utilizes the chip's capabilities to optimize LED efficiency at any brightness and minimize power consumption even when not in operation.

The most certain way to reduce the massive amount of electricity used to illuminate the streets of major cities, downtowns, and towns worldwide is to replace incandescent bulbs, low-pressure sodium lamps, and high-intensity discharge streetlights with LEDs. LEDs are fundamentally more efficient than conventional lamp technology and, above all, allow for brightness adjustment. This means that when combined with smart power supply systems, lighting output can be rapidly adjusted to suit various conditions, ranging from daylight to moonlight. Furthermore, it is possible to implement urban policies, such as controlling certain lamps at specific times.

Many cities around the world have started replacing streetlights with LED technology, and even more are in the planning stages. For example, the city of Boston, Massachusetts, had replaced 40% of its 64,000 streetlights with LEDs by the end of 2012. Currently, we are saving $2.8 million (approximately 2.96 billion KRW) in electricity costs annually, which is about 35% of the total electricity costs.

Matteo Lo Presti, ST Group Vice President and General Manager of Industrial and Power Conversion, stated, “Digital control lighting is a key factor in reducing power consumption in outdoor installations. ST’s newly launched LED street lighting solution condenses 25 years of power conversion experience into a single, future-oriented platform. In other words, all major communication protocols are already integrated with the STLUX385A, grid technology continues to become smarter, and urban lighting can be controlled in a way that further reduces power consumption.”

The reference design includes schematics, a Bill of Materials (BOM), and firmware. Therefore, customers can rapidly develop digital power controllers for 100W LED lamps using ST’s STLUX385A, the world’s first general-purpose digital controller for lighting and power conversion applications. The STLUX385A chip in this solution controls the primary regulated power conversion stage along with all supported communication links. The power conversion stage consists of a Power Factor Correction (PFC) controller followed by a Zero Voltage Switching (ZERO) LC resonant stage. High-precision brightness control is managed using the primary-side regulation (PSR) method.

The demo board provides all major physical communication interfaces, such as DALI (Digital Addressable Lighting Interface), isolated 0-10, and UART, including all communications managed by the STLUX385A chip. In addition, thanks to the flexibility of the STLUX385A, the board can be easily connected to other interfaces such as Wi-Fi, wired modems, Bluetooth®, and ZigBee®.