BQ24166: not using the USB input power supply

ajayt

Genius 9555 points

Part Number: BQ24166

I have a couple of questions:

We only intend to use the input power supply (IN) and not the USB Input Power Supply (USB). Is a requirement to use capacitors close to USB and PMIDU if the USB not used at all?
Since no power will be drawn from the USB, is the IUSB[3..1] the best configuration to suspend USB and IN to operate normally?

over 5 years ago

0 Joel Hernandez II over 5 years ago

TI__Mastermind 25800 points

Hey ajayt,

For 1. You likely do not need those capacitors if you are not using the USB input. The 1uF is a decoupling capacitor for the inputs, and the 4.7uF on PMIDU is the high frequency filtering capacitor for the buck converter.

For 2. To suspend the USB, I would just pull the pin to GND and only operate from the IN rail.

Regards,

Joel H

0 Carlos Grangeia over 5 years ago in reply to Joel Hernandez II

Prodigy 40 points

Hi Joel,

thank you for your help.

According with the threat https://e2e.ti.com/support/power-management/f/196/p/277886/971998#971998 choosing "..IUSB[3..1] = "011" is actually USB Suspend and IN operates normally. IUSB[3..1] = "111" is high impedance mode, which effectively disables both inputs.. "

Therefore, should be IUSB[3..1] = "011" the best approach to suspend the USB only?

Thanks!

Kind regards,

Carlos.

0 Joel Hernandez II over 5 years ago in reply to Carlos Grangeia

TI__Mastermind 25800 points

Hey Carlos,

Yes, that is correct.

Regards,

Joel H

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BQ24166: not using the USB input power supply