BQ35100: Query on measuring 30uA using accumulator mode

user5874521

Part Number: BQ35100

HI,

Please help to confirm if BQ35100 can be used for Li-SOCl2 Primary battery 12000mAH that for its remaining capacity measurement during operation.

Continuous load on the battery is 30uA and hourly once load current goes to 600mA(average) for a duration of few seconds.

I want to use BQ35100 to know the % of battery capacity remaining.

Is 30uA too small to measure for BQ35100 in Accumulator mode? What is the min current can BQ35100 measure in Accumulator mode?

Thanks

over 6 years ago

0 Batt over 6 years ago

TI__Mastermind 42535 points

Hi,

Yes, 30uA is too low for the gauge to measure. The gauge typically needs at least 10mA for accurate measurement.

0 user5874521 over 6 years ago in reply to Batt

Intellectual 450 points

Thank you for your reply.

I have another question about BQ35100.

When Update every 30 minutes in accumulator mode, the average power consumption is only 0.3uA? Will other parts of BQ35100 have power consumption?

In this mode, will BQ35100 increase CPU or other device's power consumption?

Does BQ35100 need to be charged? How to charge BQ35100? What is the power consumption of charge?

0 Batt over 6 years ago in reply to user5874521

TI__Mastermind 42535 points

Hi,

The power consumption referred to is the nominal consumption in sleep mode where the gauge is not accumulating charge. In normal mode it is per table 6.5. The bq35100 will not affect another device's power consumption, this is a standalone unit. The gauge supports non rechargeable batteries.

0 user5874521 over 5 years ago in reply to Batt

Intellectual 450 points

Thank you for your reply. Please help to confirm the following questions.

Can BQ35100 be used to calculate the % of battery capacity remaining in accumulator mode?

The power of system is from battery. If we use BQ35100 to monitor the battery, when BQ35100 is sleep or power off, will the whole system be power off?

0 Batt over 5 years ago in reply to user5874521

TI__Mastermind 42535 points

Hi,

No. The accumulator mode only reports total used or accumulated capacity. The whole system will not be powered off since the bq35100 does not have a FET that disconnects power when it is off.

0 user5874521 over 5 years ago in reply to Batt

Intellectual 450 points

Thank you for your reply.

In spec, recommend VREGIN supply voltage is 2.7V to 4.5V.

If I need the I2C voltage level to be 1.8V. What can I do except adding level shift circuit?

Can the power supply to BQ35100 be 1.8V? What is the funciton of REG25, can I disconnect pin REG25?

0 Batt over 5 years ago in reply to user5874521

TI__Mastermind 42535 points

Hi,

No. You can't use a 1.8V so you will need a level shifter. REG25 is the regulator pin.

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BQ35100: Query on measuring 30uA using accumulator mode