Arrow published AC/DC LED street lamp solution

To LED street an efficient automatic dimming design in power input unstable, Arrow developed to solve the LED lamp AC power input scheme based on. The scheme selection of Cree XLamp MC-E LED, NXP lighting controller PFC and flyback controller SSL1750, and the TI DC/DC constant current controller TPS40211. XLamp XR-E LED is a lighting level multi chip module, Cree LED module XR-E XLamp currently available to 5W 9W, its typical thermal resistance is 8 DEG /W. NXP SSL1750 is a switching power supply (SMPS) controller IC, suitable for LED lighting applications drive 25W to 250W. For power requirements below 25W applications, SSL152x series and SSL1623PH is more suitable. SSL1750 integrated PFC (power factor correction) controller and flyback controller, which makes the number of external components can rarely achieve cost-effective LED driving power supply. At all output power levels, the built-in special Green function ensures high efficiency. This applies to quasi resonant operation at high power levels, and to lower frequency operation at lower power levels. At low power levels, the PFC is converted to burst mode to maintain high efficiency. In burst mode, it also adds soft start and soft stop function to eliminate the audio noise. In the case of low power, the flyback controller is converted to the reduced frequency mode and the peak current is limited to 25% of the maximum value. This can minimize the transformer audio noise while ensuring high efficiency at low power. SSL1750 can make the efficiency of AC/DC conversion in more than 90%. TPS40211 is a wide input (4.5V to 52V), asynchronous boost controller, the maximum output current of 700mA, allowing the dimming way through the PWM output voltage from 20V to 37V. When the 8-18V input, the efficiency can reach 90% or more. It is suitable for the requirements of a source ground N channel FET topology (such as boost, flyback and SEPIC) and a variety of LED driver applications. Its main features include: programmable soft start, over-current protection, automatic retry and programmable oscillator frequency. Current mode control provides improved transient response and simplified loop compensation. In addition, Arrow also provides optical lens and optical solutions for LED street lights. ARR1-R60120-L1 is a special optical lens for LED street lamp, which is characterized by high efficiency, single beam pattern and consistent effect.