TPS61291: Consumption current in bypass mode but Vout > Vin

user4734074

Part Number: TPS61291

Hi,
TPS61291 does not go into bypass mode when Vout > Vin even if bypass mode is selected.
In this condition, what is the expected current consumption?

My experiment shows only several tens of nA increase to the actual bypass mode (Vout < Vin).
Is it the rational result?

Thank you.

over 5 years ago

0 Jasper Li over 5 years ago

TI__Mastermind 46905 points

why does this happen? is there an external source to power to VOUT.
do you measure the current in the input side?

0 user4734074 over 5 years ago in reply to Jasper Li

Prodigy 130 points

Thank you for your quick update.
As written in 7.4.3, page9 in the datasheet, this happens in the transient period from boost to bypass mode due to the charge of output capacitors. If the load current is very small, discharging could be slow. So I'd like to know the consumption in this period.
Yes, my measurement is at the input side.

0 Jasper Li over 5 years ago in reply to user4734074

TI__Mastermind 46905 points

what you measure is reasonable data as some internal circuit is still operating to monitor the input voltage and output voltage.

0 user4734074 over 5 years ago in reply to Jasper Li

Prodigy 130 points

OK, thank you very much.

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TPS61291: Consumption current in bypass mode but Vout > Vin