I want to control the brightness of a led which is powered by a constant current driver.

On utilizing a MOSFET and pwm signal from an arduino uno the led starts to fade in as the duty cycle increases. But the problem is that the led "blinks" at lower duty cycle and stabilizes only at about the full brightness. (The constant current driver that came with led is used here).

Please suggest me a new circuit in which I am able to avoid the blinking issue while utilizing the driver that came with the led.

Also, take a look at this : how to control constant current led driver output with pwm?

enter image description here


simulate this circuit – Schematic created using CircuitLab

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    \$\begingroup\$ What's the frequency of your PWM? \$\endgroup\$ – Eugene Sh. Jan 24 at 18:04
  • \$\begingroup\$ The frequency is 980Hz \$\endgroup\$ – Electric_90 Jan 24 at 18:05
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    \$\begingroup\$ "Constant current" driver is making me suspicious. How can it be constant if you are breaking it with the MOSFET? The idea of using the driver is that you can control it to change the current and the brightness. \$\endgroup\$ – Eugene Sh. Jan 24 at 18:06
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    \$\begingroup\$ Most constant current LED drivers I've seen have dimness control at the driver itself - something that throttles the output between 0 and 130mA. Many are I2C/SPI controlled, but you might find one that accepts PWM as a control signal. \$\endgroup\$ – Chris Fernandez Jan 24 at 18:08
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    \$\begingroup\$ You should tell us more about this driver. \$\endgroup\$ – Eugene Sh. Jan 24 at 18:11

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