TPS61199: The relation between OVP and LED bar Vf

user5923617

Part Number: TPS61199

I am using a TPS61199 to make a LED driver board to drive LED bar.

The issue is that I set the OVP=60V, it is OK when the LED bar Vf=54V, however the LED bar will flash if Vf=27V(Reduce the LED quantity).

Is there a limitation between OVP setting and real LED bar Vf?

0 Sean Zhou over 5 years ago

Hi Sir,

Yes, you can't set the OVP too far from the real LED bar Vf, we usually set the OVP=1.2* maximum LED bar Vf.

Regards

Sean

0 user5923617 over 5 years ago in reply to Sean Zhou

Hi Sean

Thanks for your quick response.

"OVP=1.2* maximum LED bar Vf" , how to understand the maximum LED bar Vf?

For example, my LED bar Vf range is(52V-56V), the OVP should be set as 56V*1.2=67.2V or 52V*1.2 62.4V?

If I set OVP=67.2V, can the LED bar which Vf=52V work normally?

Thanks.

0 Sean Zhou over 5 years ago in reply to user5923617

Hi sir,

Yes, your understanding is right.

Regards

Sean

0 user5923617 over 5 years ago in reply to Sean Zhou

Hi Sean

Sorry I am a little confused.

If my LED bar Vf range is(52V-56V), the OVP should be set as 56V*1.2=67.2V or 52V*1.2=62.4V?

Which one is the right setting?

0 Sean Zhou over 5 years ago in reply to user5923617

Hi Sir,

Sure. it should set the OVP to 67.2V.

Regards

Sean

0 user5923617 over 5 years ago in reply to Sean Zhou

Thanks Sean

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