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LED making a high-pitched ringing noise

Victor · 2017-08-25 21:19:44

I bought an LED bulb for a table lamp and I am getting a high-pitched ringing noise when it is on. I know florescents and some CFLs make noise, but is this usual?

25-08-2017 9:19pm

#1

Victor

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I bought an LED bulb for a table lamp and I am getting a high-pitched ringing noise when it is on.

I know florescents and some CFLs make noise, but is this usual?

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#2 25-08-2017 10:33pm

Steve

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No, not usual but not unexpected.

All LED's ultimately operate on approx 0.7V DC, the method of dropping mains 240V AC to that varies greatly. The fact you can hear a noise would suggest a capacitor / resistor network is being used.

Can you post a link to the model / part#?

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#3 26-08-2017 12:28am

Victor

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Osram

LED Star
Classic A60
E27

8W = 806 lm

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#4 26-08-2017 2:39pm

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PWM carrier frequency possibly too.
Lazy engineering using audible wavelengths.

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