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led driver schematicIf I connect the positive output of a LED driver to anode and cathode of LED is connected to power ground (Negative output of driver is remain unconnected), whether the LED Will work or not?

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  • \$\begingroup\$ Probably not. But it might work, or it might glow dimly, depending on the design of the LED driver. \$\endgroup\$
    – Simon B
    Commented Sep 27, 2018 at 12:54
  • \$\begingroup\$ Lm3410 is using as driver. can you say it will work or not \$\endgroup\$
    – shafeeq
    Commented Sep 27, 2018 at 12:57
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    \$\begingroup\$ It won't work correctly, because you will be bypassing the feedback resistor that the LM3410 uses to sense the current. I wouldn't like to predict what would happen. \$\endgroup\$
    – Simon B
    Commented Sep 27, 2018 at 13:04
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    \$\begingroup\$ I like the "Corrupted Virus" on the lower right corner \$\endgroup\$ Commented Sep 27, 2018 at 13:05

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You would be eliminating the control circuit and the NMOS protection circuit when the Feed Back pin is bypassed.

Either the LED or the NMOS switch will blow. The resistor is a small ≈4Ω sense resistor not a current limit resistor.

7.3.1 Current Limit
The LM3410 uses cycle-by-cycle current limiting to protect the internal NMOS switch. This current limit does not protect the output from excessive current during an output short circuit. The input supply is connected to the output by the series connection of an inductor and a diode. If a short circuit is placed on the output, excessive current can damage both the inductor and diode.
-- LM3410 Datasheet

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