I am new to building circuits. I am running the following LED circuit:

Circuit diagram

When I plug it in, there is an occasional "pop" of the LED. Does the circuit need something like a diode to prevent a current kickback? Or something else?

  • \$\begingroup\$ Are your LEDs rated to 1A? \$\endgroup\$ Oct 23 '13 at 13:08
  • \$\begingroup\$ The LEDs are CXA2520's, According to the data sheet, the maximum DC forward current is 1.25A whereas the LDD provides a 1A constant current. \$\endgroup\$ Oct 24 '13 at 11:48
  • \$\begingroup\$ Are your LED's on any sort of heat sink? \$\endgroup\$
    – John U
    Oct 24 '13 at 13:45
  • \$\begingroup\$ Yes. I use CPU heat sinks. The temperature is at about 86F \$\endgroup\$ Oct 24 '13 at 14:02

Should I add something to prevent kickback on this LED circuit?


There shouldn't be any "kickback" in that circuit.

The power supply looks like a Mean Well S-350-27 which puts out 27V at up to 13A.

As Pete suggests in a comment, the cause of 'an occasional "pop" of the LED' is likely to be that the Mean Well LDD-1000H constant-current LED driver (1000 mA output) exceeds the current rating of the LED module whose maker name and part number you are keeping a secret ;-)

As I understand it, a constant current driver like the LDD-1000H will increase Vout from 2 up to 52V until the current is approximately 1000 mA. If the LED module is rated 45V max (for example) but draws less than 1000mA, I would expect there will be a problem.

  • \$\begingroup\$ as noted on my comment to Pete - I am using CXA2520 LEDs. The forward voltage has a typical value of 36V and max value of 42v. As noted above, the DC forward current is 1.25 A max. So doesn't it draw more than 1 A thus not fitting the scenario for problem? \$\endgroup\$ Oct 24 '13 at 11:51

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