STMicroelectronics announces intelligent LED streetlight controller

Feb. 13, 2014
SSL driver reference design based on the STLUX385A digital power controller that integrates an STM8 microcontroller enables networked LED streetlight designs with a choice of interfaces and adaptive control scenarios.

STMicroelectronics has announced the STEVAL385LEDPSR evaluation board and reference design for intelligent LED-based streetlight designs. The design includes the STM8-microcontroller-based STLUX385A digital power controller IC that can implement the solid-state lighting (SSL) driver functionality and provide a variety of interfaces including network connectivity.

Many industry experts have suggested that networked outdoor lighting is simply a necessity as the global population expands and the population growth is especially acute in major cities. We covered such sentiment at the 2012 Street & Area Lighting Conference expressed by Philips executive Niels Van Duinen in a keynote. Also watch for a feature in our February issue that covers similar presentations made at the Strategies in Light Europe conference. LEDs save energy but adaptive controls are needed for maximum savings.

STMicroelectronics sees things similarly. "Digitally controlled lighting is the key to saving energy in outdoor installations," said Matteo Lo Presti, group vice president and general manager for the Industrial and Power Conversion Division of STMicroelectronics. "ST's new solution for LED streetlighting packs 25 years of experience in power conversion into a single, future-proof platform. As grids get progressively smarter, cities will be able to control the streetlamps to produce even greater savings because all the key communications protocols are already incorporated in the STLUX385A."

The company's reference design enables SSL streetlight manufacturers to quickly bring intelligent designs to market. STMicroelectronics will supply the design with full schematics, a detailed bill of materials, and the required firmware. The STLUX385A IC can handle both the power-regulation stage on the primary side of an AC/DC driver along with implementing smart features and adaptive controls.

Indeed, the STLUX385A IC integrates full support for a DALI (digital addressable lighting interface) network link. The peripherals integrated with the microcontroller can enable implementation of 0-10V analog controls and also interface with a variety of sensors. Digital communications facilities on chip allow for a development team to add Wi-Fi, ZigBee, and other network support with external ICs.

The evaluation board allows development teams to immediate experiment with SSL system designs using a fully operational driver. The design is capable of dimming based on programmatic or sensor control. Moreover, the design includes a power-factor conversion regulator followed by a zero-voltage-switching resonant stage that together with the STLUX385A comprise the complete LED driver functionality.

STMicroelectronics is selling the evaluation board/reference design for $140. Development teams can purchase the product on the company's website.