TPS54200: PWM dimming frequency range

Hyun woo Kim1

Intellectual 440 points

Part Number: TPS54200

Dear TI members,

could you let me know that below question.

(1) PWM dimming frequency range during Analog dimming mode

(2) PWM dimming frequency range during PWM dimming mode

there is no range in datasheet.

Best regards,

over 2 years ago

0 Mason Wang over 2 years ago

TI__Genius 9630 points

hi kim

considering current accuracy and linearity, the recommended PWM frequency for analog dimming is larger than 10kHz and frequency for PWM dimming is smaller than 1kHz.

0 Hyun woo Kim1 over 2 years ago in reply to Mason Wang

Intellectual 440 points

Thank you for reply.

isn't there any min / max range ?

Best regards,

+1 Mason Wang over 2 years ago in reply to Hyun woo Kim1

TI__Genius 9630 points

hi Kim

For analog dimming, the reference is generated by a RC filter, so normally higher PWM frequency is preferred, so there is not a specific max. value here.

For PWM dimming, due to the limitation of loop response, low frequency operation is easier to realize. One thing needs to notice with extremely low frequency like 100Hz or even smaller is the possibility to trigger BOOT UVLO when off time is too long. This can be solved by increase Boot cap to 0.2uF or more.

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TPS54200: PWM dimming frequency range