4. For a particular LED lighting design, how do you select a suitable power supply?
4.For a particular LED lighting design, each LED strip consists of 12 LEDs connected in series (VF=3.5V), 4 strips in parallel, and each strip requires 0.7A of drive current. Based on the above conditions, how do you select a suitable power supply?
First of all, the LED power supply must be able to work in constant current mode. LED forward voltage of each strip = 3.5V X 12pcs = 42V
LED lamp total current requirement = 0.7A X 4 strips in parallel = 2.8A
LED power requirement = 42V X 2.8A = 117.6W
LED power supply's rated voltage/power should be greater than what is required but should be as close to the actual requirement as possible.
Use 48V/150W as the basic criteria to pick LED power supply then make sure actual voltage/power usage meets constant current region and PF>0.9 specifications (117.6W/150W = 78.4% > 75%).
CLG-150A-48V with output current set at 2.8A can be used in this design.
Note: Each LED production lot will fall within a VF rank (e.g.3.4~3.6V). This LED tolerance must be taken into consideration during design.
fall within a VF rank (e.g.3.4~3.6V). This LED tolerance must be taken into consideration during design.
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