LP55281: Quiescent Current Calculation

Michael Balourdas

Part Number: LP55281
Other Parts Discussed in Thread: LP5012, LP5024

Hello,

Just want to make sure I'm calculating the Iq for this part correctly. If I have all EN_RGB HIGH, and ALED and Audio Sync disabled, would my Iq be 0.6mA + 250uA = 850uA?

Thanks,

Michael

over 2 years ago

0 Ives Li over 2 years ago

TI__Expert 6440 points

Hi Michael,

Your understand is correct, so is your customer considering the supply current for their application?

Besides, I'm curious about why customer choose LP55281, is it because they need the boost function?

If the boost function and Audio Sync function is not necessary for their application, I recommend LP5012 for them, it will be cheaper than LP55281.

Thanks!

Ives.

0 Michael Balourdas over 2 years ago in reply to Ives Li

TI__Expert 5385 points

Hi Ives,

Thank you for the information. They want to use LP55281 because the Iq is lower than LP5012. Do you know what that's the case? LP5012 is much newer so I'm surprised it's so much more power hungry.

Also, if we're not using the boost function of LP55281 and instead using an external supply, should SW and FB be grounded or left floating?

Thanks,

Michael

0 Ives Li over 2 years ago in reply to Michael Balourdas

TI__Expert 6440 points

Hi Michael,

If the boost function is not used, please left it SW and FB floating.

But if the boost function is not used, I still suggest you with LP5024.

With new device we can provide better support and the cost is lower than LP55281.

Besides, LP5024 is much easier to use.

Please consider my suggestion and recommend LP5024 to customer .

Thanks!

0 Michael Balourdas over 2 years ago in reply to Ives Li

TI__Expert 5385 points

Hi Ives,

Customer wants to use LP55281 because the Iq is significantly lower. Why is the Iq of LP55281 so much lower than LP50xx?

Thanks,

Michael

0 Ives Li over 2 years ago in reply to Michael Balourdas

TI__Expert 6440 points

Hi Michael，

Even the Icc value in datasheet shows difference between two device，but I think it is not the main power consumption during the application. So it will not show big different for them，but if use LP50xx，their cost could be much lower than LP55281.

Thanks！

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LP55281: Quiescent Current Calculation