An energy-efficient LED street lighting solution

Fairchild Semiconductor has developed a complete LED street lighting solution that features high energy efficiency, excellent thermal performance, and high reliability to extend the life of street lamps.

This performance-optimized solution reduces power consumption and meets stringent energy efficiency standards and requirements of government agencies around the world, including the Chinese central government and provincial agencies, as well as ENERGY STAR? Solid-State Lighting (SSL) guidelines; while also addressing the growing consumer and market demand for more environmentally friendly electronic products, further demonstrating Fairchild Semiconductor's leadership in high energy efficiency.

Fairchild Semiconductor's new street lighting solution features advanced critical conduction mode (CrCM) PFC, high-efficiency DC-DC conversion and constant current control, and includes two parallel or serial sub-solutions in the same PCB layout. From AC input to LED end, it can provide up to 91.26% (parallel) and 92.6% (serial) energy efficiency at 220V input voltage.

The current of each LED string in the parallel solution is controlled individually, so if one LED string is open-circuited, the remaining LED strings can still operate normally. For the serial solution, each LED string has an independent open-circuit protection function, so if one LED is open-circuited, the remaining LED strings can still operate normally. In addition, if one LED is short-circuited, the constant current circuit can ensure that all other LEDs in the parallel and serial sub-solutions operate normally.

Compared with traditional solutions, this new solution can significantly reduce the number of components, reducing more than 20 components in parallel layout and 86 components in serial layout. This solution has a lower number of components, powerful protection functions and high LED fault tolerance, so it is very reliable. When developing this overall solution, Fairchild Semiconductor GPRC engineers selected a series of parts from the company's rich product line, such as the active power factor correction (PFC) controller FAN7930 to perform boost PFC applications under CrCM, and the highly integrated Fairchild Power Switch (FPS?) product FSFR2100 provides all the functions required to build a reliable and robust resonant half-bridge converter.

In addition, Fairchild Semiconductor has a variety of LED lighting solutions for applications with output power ranging from 7W to over 100W, including:

Standalone PFC controllers and PFC/PWM combo controllers, as well as PFC controllers using Critical Conduction Mode (CrCM) and Continuous Current Mode (CCM) techniques, are designed to improve system efficiency, reduce system noise, and provide a range of protection features for medium and high power designs

PWM controllers, including standalone and highly integrated solutions with MOSFETs, such as the asymmetric half-bridge controller FSFA2100, including LLC resonant controller FAN7621, and standalone LLC resonant controller FAN7621

Primary-side regulation (PSR) PWM controllers, such as FSEZ1317, FSEZ1317, and FAN103, enable precise constant current (CC) control and simplify circuit design

Broad portfolio of high voltage MOSFETs, rectifiers and diodes