High efficiency controller solutions for LED lighting
Two new QR PSR PWM controllers for LED lighting with Power Factor Control (PFC) function have been announced by ON Semiconductor. The dimmable NCL30386 and the non-dimmable NCL30388 provide options for designers of LED lighting units such as luminaires used in office and industrial building applications.
Both devices are high power factor (PF), single stage, constant current (CC) and constant voltage (CV) primary side regulated (PSR) pulse width modulation (PWM) controllers for Flyback, Buck-Boost or Sepic power topologies. They operate in Quasi-Resonant (QR) mode to achieve efficiency levels that exceed those stipulated in power standards such as the EU’s Ecodesign as well as ENERGY STAR and the NEMA SSL regulations.
The integrated digital power factor correction (PFC) algorithm ensures a PF of greater than 0.95 and total harmonic distortion (THD) of less than ten percent across a universal input voltage range. Integrated high voltage startup current source ensures fast startup, low standby power and wide range operation at the output. Current and voltage are regulated via a digital PSR CC/CV loop control, typically achieving in the region of ±2%, to give highly uniform lighting brightness under all conditions.
The devices are simple to use and operate from a wide VCC range of 9.2-26VDC, with valley lock-out and frequency foldback ensuring high efficiency across the entire voltage range. Design is further simplified by the inclusion of safety features such as brown-out and overvoltage protection plus the ability to detect short circuits in the output, winding and diode.
Neither the NCL30386 nor the NCL30388 require many external components to complete the design, reducing time-to-market, BoM cost and the space required to realise a complete lighting solution. Additionally, the NCL30386 offers supposedly excellent dimming features, including the option for either linear or quadratic dimming curves. The wide analog dimming range is controlled by two dedicated analogue/PWM control pins that allow for precise dimming with a 0.5% minimum dimming ratio - and no audible noise present.
Commenting on the new releases, Ryan Zahn, Director of Marketing and Applications for the AC/DC Business Group at ON Semiconductor said: “Due to its low power credentials, LED lighting is an important sector and efficient operation is critical to manage costs in the face of rising energy prices and heightened environmental considerations.
"Our new solutions not only deliver market-leading efficiency but also offer designers a high degree of flexibility and the ability to meet and exceed the requirements of prevailing efficiency standards. The designer’s task is simplified by the wide range operation, low standby power and fast startup. Additionally, the NCL30386 offers very precisely controlled dimming across a wide range, making it an ideal solution for smart lighting installations.”
The NCL30386 and the NCL30388 will be in full production in Q1, 2018.