BQ34Z100-G1: Low standby current setting in ship mode

Edward Lee

Intellectual 1655 points

Part Number: BQ34Z100-G1
Other Parts Discussed in Thread: BQSTUDIO

Hi Team,

My customer designs the battery pack with our gauge BQ34Z100-G1.

They would like to know how to set the gauge in ultra low standby current.

Is setting to full sleep mode the lowest standby current?

Thanks

Sincerely,

Edward

over 5 years ago

0 Andy Liu (BMS) over 5 years ago

TI__Guru 52115 points

The bq34z100-g1 device has three power modes: NORMAL mode, SLEEP mode, and FULL SLEEP mode. The FULL SLEEP mode can achieve the lowest power consumption.

See Chapter 5 fo bq34z100-g1 TRM for more details.

Andy

0 Edward Lee over 5 years ago in reply to Andy Liu (BMS)

TI__Intellectual 1655 points

Dear Andy,

If we want to set bq34z100-g1 into FULL SLEEP mode, we should not only set the corresponding control command but also modify the data flash too?

That is to set the Full Sleep Wait Time larger than 0. Is this correct?

Thanks

Sincerely,

Edward

0 Andy Liu (BMS) over 5 years ago in reply to Edward Lee

TI__Guru 52115 points

Yes. The correct parameter is called "FS Wait" in the bqStudio. By default, it is 0, which means the FULL SLEEP mode is disabled. You need to set it to a non-zero value to enable the FULL SLEEP mode.

Andy

0 Edward Lee over 5 years ago in reply to Andy Liu (BMS)

TI__Intellectual 1655 points

Hi Andy,

Would you mind we ask more questions?

I tried to list the questions below.

1. How to disable FULLSLEEP ? Do we have sample codes for reference?

The customer successfully set FULLSLEEP but they found it cannot be disabled either by bqStudio or I2C command sets from the host IC.

2. Do we have the sample codes for accessing flash data memory?

The command sets should be (1) Unseal (2) Change the value of FS Wait (3) Seal

It is easy to modify through Bqstudio but the customer wants to modify it by their software in linux.

Thanks

Sincerely,

Edward

0 Wyatt Keller over 5 years ago in reply to Edward Lee

TI__Guru** 105590 points

Hello Edward,

As Andy mentioned, when the FS Wait is set to 0 in dataflash the mode should be disabled, you can change the value in the data memory section of bqStudio. If you are trying to implement the commands with an MCU you can use a logic analyzer or scope to check the communication bqStudio does for the commands you have questions about.

You can also check the app note Gauge Communication: https://www.ti.com/lit/an/slua801/slua801.pdf?ts=1597260360423&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FBQ34Z100-G1

Which outlines some standard communication in C.

Sincerely,

Wyatt Keller

0 Edward Lee over 5 years ago in reply to Wyatt Keller

TI__Intellectual 1655 points

Hi Wyatt,

Thanks for your feedback.

I can help to scope the commands for the customer.

There is one more question about "disable FULLSLEEP" command.

We only can see the "Set_FULLSEELP" command in bqStudio while cannot find the command to disable it.

Would you kindly to advise?

Sincerely,

Edward

0 Wyatt Keller over 5 years ago in reply to Edward Lee

TI__Guru** 105590 points

Hello Edward,

This command should enable the FULLSLEEP functionality, but to see if the gauge has entered that full sleep mode you have to check the current consumption as stated in section 5.3 FULL SLEEP Mode of the TRM.

It will have to transition from SLEEP mode to FULLSLEEP mode, you should see a decrease in current consumption.

It doesn't look like there is an easy way to tell if it is enabled or disabled from the registers. If the full sleep wait time is set to 0 it is disabled.

Sincerely,

Wyatt Keller

Power management

Power management forum

BQ34Z100-G1: Low standby current setting in ship mode