With the availability of high intensity LEDs, LED lamps can be designed using lesser number of LEDs and also off-the-shelf LED drivers. Lesser number of LEDs means less PCB space and less heat sink cost. Here we give example of high intensity LED and a latest LED driver for street lights.
The new XLamp XHP35 family of LEDs from Cree generates 50 percent more light output than Cree’s previous highest-performing single-die LED. XHP35 LED generates a light of 1,833 lumens. XHP35 LED need lower drive currents.
XHP35 family of LEDs uses 12V monolithic power die with drive currents at or less than 1A. XHP35 High Density LED is suggested for high lumen applications, such as outdoor and high bay lighting and also in stadium, torch and track lighting.
The XHP35 LEDs are available in 70, 80 and 90 CRI and color temperatures ranging from 2700K to 8300K with 2-step and 3-step EasyWhite options.
Visit www.cree.com/xhp for more information on Cree XLamp XHP LEDs.
New LED Driver: Power Factor corrected Quasi-Resonant PWM controller HT7L5821 from Holtek is suitable for applications such as outdoor street lighting and ceiling lamps for indoor illumination. HT7L5821 has functions such as valley detection, green mode and the power compensation.
The protection functions available in this device includes secondary side open circuit protection, over current protection with a self-recovery function, adjustable over temperature protection and internal over temperature protection by using an external NTC resistor. Additional protection features include over voltage protection for the VCC input and the DET output and AC input voltage Brown-in/out protection.
The device is supplied in a 16-pin NSOP package.