LM36011: Will the input voltage need to be higher than the LED VF?

Ronald Wang

Part Number: LM36011

Dear Sir,

Will the input voltage need to be higher than the LED VF?

e.x

Vin=4.5V LED Vf=4.5V

Question 1 :Does the above example LM36011 drive the LED normally?

Question 2:How much does Vin need to be bigger than Vf if question 1's answer is NO?

Thank you.

Best regards,

Ronald

0 Harini Sankabattula over 5 years ago

Hi Ronald,

Please look at Vhr specification in the LM36011 datasheet on Page # 5.

The headroom need to be 550mV for 1.5A and 350mV for 376mA. In other words, Vin need to be higher by Vhr to drive the LED normally.

Hope this answered your questions. Please let me know if there are more questions.

Best,

-Harini

0 Ronald Wang over 5 years ago in reply to Harini Sankabattula

Dear Harini,
Thank you for your great help.

Best regards,
Ronald

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