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MAX1555 With system current draw

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New Member
Has anyone used a MAX1555 with a significant system current draw?

I'm planning on using one to charge a battery in circuit via USB(see diagram below). I want to use my LCD output to display current charging information however I know that the PIC + LCD is going to be about ~25ma. Is this something I should worry about? I was thinking of going with just a simple SMD LED but those are still around 10-15ma.



Well-Known Member
If the current draw from the USB port is less than 100 mA, you should be fine. In practice The USB port host rarely turns off port power due to failed enumeration from lack of communication with the device being powered.

That is why there are USB powered reading lights, coffee mug warmers, etc. that have no communication capability. They may not be "compliant," but they do function.

I did not review your circuit, but address the current draw issue only.
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