• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 444 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Original question:

BQ25120AEVM: could not activate "Active Battery Mode" on EVM

BQ25120AEVM: Is there any method to measure current consumption of the chip?

Hyobin Yang
Prodigy 60 points
Part Number: BQ25120AEVM
Other Parts Discussed in Thread: BQ25120A, BQ25121A

Hello.

I'd like to measure the current consumption of the IC to verify the number suggested by datasheet.

I am powering the EVM with SMU 5V with no load on DC/DC converter output.

With Vsys 1.8V it consumes 1.66mA(without charging, load) but if I set Vsys 2.5V it consumes 2.6mA.

So far there's some current consumption through LED, resistors etc. but it seems that internally there's something that I cannot see via datasheet of EVM.

Is there any method to measure the current consumption of bq25120a on idle state with EVM?

Regards,

Hyobin 

  • 0
    TI__Genius 12485 points
    Hyobin,

    You will need to disconnect the BQLED jumper and I2C pullup jumper to measure Iq. Also make sure no load on PMID/ VINLS as well.

    Are you connecting to VIN?

    regards,
    Gautham
  • 0 in reply to Gautham
    Prodigy 60 points
    Thanks Gautham,

    Well, I have some more question about the behavior of this IC with battery.
    I tested bq25121A with solid-state battery.
    I've set Vbat_uvlo as 3.0V and I checked that once the battery voltage falls below 3.0V the protection circuit reacts and the circuit was running by high-z mode.

    So, the problem is that once the load is disappeared, the battery voltage should rise up to 3.8V(floating voltage) but maybe because of the hysteresis characteristics it cannot recover its floating voltage. Instead, the voltage goes up to 3.15~3.17V and then it discharges again until the voltage falls below 2.0V

    My question is below:

    1. What is the exact state right after the Vbat_UVLO protection when the IC has been running by High-Z mode?

    2. The only way to latch-off the battery from the IC is ship mode?


    Thanks in advance.

    Regards,
    Hyobin
  • 0 in reply to Hyobin Yang
    TI__Genius 12485 points
    Hyobin,

    Please create a new thread as that will help out closing old ones :)

    When VBATUVLO is reached, the device will turn off the BATFET. Ship Mode is the best way to disconnect the system load from the battery.

    The device will not be in HiZ mode as the HiZ mode will have the DC-DC running and PMID powered by the battery. Also the other requirement for HiZ Mode is for VBAT to be greater than VBATUVLO.

    You could adjust VBATUVLO register if you want to allow for a deeper discharge with a high impedance battery. Or you can momentarily reduce VBATUVLO before you turn on a large load (such as haptics etc.,) and then turn it back to 3.0V as well.

    regards,
    gautham