09/09/2025 4:56 am
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How does PWM frequency affect motor speed control and LED dimming? For motors, does changing the frequency make any difference in smoothness or efficiency? And for LEDs, how does frequency impact visible flicker or brightness perception? I’m also interested in knowing what frequency ranges are generally recommended for these applications.
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10/09/2025 4:56 am
PWM frequency doesn’t change the basic control of speed or brightness (that’s handled by duty cycle), but it does affect how smooth and practical the control feels.
For DC motors, too low a frequency can cause audible whining and jerky torque, while using a frequency in the 2–20 kHz range keeps operation smoother and moves the noise above the human hearing range. Going too high can reduce efficiency due to increased switching losses.
For LEDs, low frequencies below ~100 Hz cause visible flicker, which is unpleasant and can be noticeable on cameras as well. Frequencies in the 200–500 Hz range reduce flicker significantly, but for professional lighting or display applications, 1 kHz and above is generally preferred to ensure flicker-free performance.
