LM3642: LED efficiency data under VIN=2.5~3.5V

K.Yaita

Part Number: LM3642

Hi Team,

I would like to ask two questions.

1)
I believe the following LED efficiency include the efficiency of boost converter.
Is my understanding correct?

2)
Does TI have the LED efficiency data under VIN=2.5~3.5V (especially VIN=3.0~3.5V)?

Best Regards,
Yaita / Japan disty

over 7 years ago

0 Greg Lubarsky over 7 years ago

TI__Intellectual 1940 points

Hello,

1) Yes this includes efficiency of the boost and the current source.

2) Here is the 1.5A efficiency plot with the extended VIN range. Please note that while the efficiency does not drop, the LED current does due to the device hitting the inductor current limit.

Regards,

Greg

0 K.Yaita over 7 years ago in reply to Greg Lubarsky

Guru 29720 points

Hi Greg-san,

Thank you for your kind support!
I believe LED current (red) and LED efficiency (blue) is reverse because the efficiency feature is different from Figure 18.
Is LED Efficiency red prot?

Best Regards,
Yaita

0 Greg Lubarsky over 7 years ago in reply to K.Yaita

TI__Intellectual 1940 points

You are correct. I had the labels swapped. Here is the corrected plot.

Greg

0 K.Yaita over 7 years ago in reply to Greg Lubarsky

Guru 29720 points

Hi Greg-san,

I appreciate for your kind support!

Best Regards,
Yaita

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LM3642: LED efficiency data under VIN=2.5~3.5V