LM3409: PWM Dimming Using EN Pin

Sadanori Kato

Part Number: LM3409

Hi,

Could you please tell me the recommended dimming frequency range(min/max) if EN pin is used for PWM dimming of the LED ?
Our customer is considering to using at 120Hz as the dimming frequency.

Best regards,
Kato

over 7 years ago

0 Irwin Nederbragt over 7 years ago

TI__Mastermind 28655 points

Hello Kato,

If using the EN pin the PWM off-time is limited by VCC discharge, 120Hz is fine, it will work even lower than this. If the off-time gets to be too long then using UVLO for the PWM input makes more sense. It is capable of long PWM off-time.

Regards,

0 Sadanori Kato over 7 years ago in reply to Irwin Nederbragt

Guru 36540 points

Hi Irwin-san,

Thank you for your quick response.

I understood.

Best regards,
Kato

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LM3409: PWM Dimming Using EN Pin