LED Lighting Power Supplies
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LED lighting offers users an efficient, safe and reliable lighting power solution. LED’s are fast becoming the prefered lighting choice of so many applcations because you get more light per watt, have the ability to turn on/off quickly, there are more colour options and they have a long lifespan. To meet this demand an increasing range of LED lighting power supplies is now available on the market.
Sunpower UK’s lighting power supply range varies in size and capacity helping you get the right power supply for your application. Whether you are looking for a internal light fitting solution or a weatherproof solution capable of powering long strings of lights we have a LED lighting power supplies solution to suit.
LED Lighting System Designs
Setting | Circuit Diagram | Description | Advantages & Disadvantages |
Constant Current mode Power Supplies No need for a ballast resistor and LED driver IC |
For 1W LED, VF=3.2V, I F=0.35A Parallel connection: 6.3A/0.35A=18 18 branches need to be connected in parallel |
Using lighting power supply as the constant current source and feed the LED arrays directly | Advantages: Low cost Less complex Only need to consider LED characteristics.Disadvantages: Driving current may be unbalanced for each branch. |
Constant current region of CLG-150-24: 12~24V. The LED series connection should be 4 to 7. |
PF>0.9 only for 75% of rated load or higher, the recommended series connection is 6 or 7. | ||
Constant Voltage mode Power Supplies Add ballast resistor to balance each brance of LED’s |
R=[V-(VF1+VF2+…+VFn)]/IF Note: V : Rated output voltage of LED power supply VF: LED’s forward voltage I F : LED’s forward current |
Example: Using LPV-60-24 (24V/2.5A)to drive a LED array which 6 LEDs connected in series in each branch and 4 branches connected in parallel R= [24-(6×3)]/(2.5/4)=10Ω |
Advantages: Low cost Less complexDisadvantages: Brightness of LED can be uneven Poor efficiency |
Constant Voltage mode Power Supplies Driver IC is used as a constant current source (without ballast resistor) |
PWM constant current source will regulate forward current to achieve even current at each branch | Advantages: High efficiency Perfect current balance to each branch Longer lifetime for LEDsDisadvantages: Higher cost High complexity EMC problem at lighting equipment side |