Posted on: September 10, 2014

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
Suggested Circuit Diagram for Constant Current mode LED Lighting Power Supply System
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
Suggested Circuit Diagram for Constant Voltage mode LED Lighting Power Supply System
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)
Suggested Circuit Diagram for Constant Voltage mode LED Lighting Power Supply System 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

View Sunpower’s LED Lighting Power Supplies