I have a project where I want to power several LEDs with a small LED Driver. These are plain 5mm, 3v, LEDs, the driver is a constant current 250ma driver. I am using three LEDs with a small resistor to reduce the voltage a bit to 2.7v.
The problem is that the LEDs flash at about 2 flashes/second very consistently. I am unable to figure out why.
I have several of these LED drivers with various outputs, and all of them do the same thing (with different resistors).
I have tried adding a capacitor to the circuit at various points (sometimes several) with no apparent effect.
I must be missing something. Any ideas how to make the LEDs steady?
What driver model, and what are you powering them with?
Based only on the very limited info provided, the driver might not be getting/giving enough juice for adequate power, or the power supply is set to pulse or AC? If the supply is adequate, try adding a simple rectifier to ensure it’s DC.
Try it without the resistor but with more LEDs or higher Power LEDs.
If it’s a real driver and not just a power supply, the resistor is just f-ing up all of what the driver is made for.
The driver delivers 250mA in a range of voltage, not exactly 3v and 250mA.
Are you sure they’re plain 5mm leds and not the blinking kind? Can you come up with a way to test them without the driver to confirm the driver is the issue?
The LEDs are plain 5mm (not flashing, tested with 3v battery). I have used the same LEDs as replacements in various devices such as LED lamps, nightlights, etc. and they all work normally.
I have tried multiple drivers (image attached). All of the drivers exhibit the same flashing issue.
I have tried single, to multiple LEDs (13 total) in both series and parallel, with and without various resistors.
Have you tried different outlets? Perhaps your outlet is “dirty”. Are you going directly into the wall with the driver? Are you hardwiring in? Are you testing on a power supply machine?
Yes, to all. My test bench also has a dedicated outlet with no other items connected.
Currently I am using a breadboard with a 120VAC switched connection. I have tested the input and output voltages with the Fluke meter during every test. The AC varies between 118VAC and 121VAC, but is generally very consistent depending upon the time of day.
The DC end I just plug the meter in during the entire test. The output voltage is generally very stable within the reaction time of the meter.
