BQ78350-R1: IPScale-ing not working, but does it affect in any way.

Janar Plinkner

Part Number: BQ78350-R1
Other Parts Discussed in Thread: BQ78350,

Hi,

I know there is a bug that the IPScale-ing bits do not work and it does not scale the current related parameters but my main question is if it affects anything when I set the bit to scale 10x. I will scale manually at the calibraton stage my self. If the IPScale-ing does not affect any internals then that is good, so I can use it as a flag to indicate that the currents and other related parameters are scaled 10 times.

Also will there be an update for the firmware to correct this bug?

Janar

over 6 years ago

0 Onyx Ahiakwo over 6 years ago

TI__Guru* 76230 points

Hi Janar
Are you referring to the bq78350 or the bq78350-R1 firmware version. Where did you get the info from that the Ipscale doesn't work??
thanks
Onyx

0 Janar Plinkner over 6 years ago in reply to Onyx Ahiakwo

Prodigy 70 points

Hi Onyx,

I got the info on how to do manual scaling from here: https://e2e.ti.com/support/power_management/battery_management/f/180/t/524477

And I have tried the Current scaling bits to use it but the current does not scale.

I should have the BQ78350-R1-s. But I have not tried to upgrade it with the firmware that is on the product page yet. The Firmware is dated at 2015 but that post is from 2016.

Kind Regards,

Janar

0 Onyx Ahiakwo over 6 years ago in reply to Janar Plinkner

TI__Guru* 76230 points

Hi Janar
Pls update the firmware to the R1 version
thanks
Onyx

0 Janar Plinkner over 6 years ago in reply to Onyx Ahiakwo

Prodigy 70 points

Hi Onyx,

On my test device, I read the firmware version and build number, it was the latest but I still upgraded the firmware and the issue is still present.

The Voltage Scaling works as expected. When scaling voltage by 10^1 then the pack Voltage register shows a correct value, (real value divided by 10).

But the Current scaling still shows real current and is not divided by the scaling factor.

Janar

0 Onyx Ahiakwo over 6 years ago in reply to Janar Plinkner

TI__Guru* 76230 points

Hi Janar
Yes, you are right. I confirmed with the system engineer that at this time, the current scaling doesn't work on the device. This will be fixed in a later firmware release.
thanks
Onyx

0 Janar Plinkner over 6 years ago in reply to Onyx Ahiakwo

Prodigy 70 points

Hi Onyx,

Yes I know about this, but my main question is that is it safe to set the bits to indicate the host that there is scaling involved or will the bits interfere somehow in the firmware.

I would manually scale all the necessary registers before/after setting the current scaling bits.

Janar

0 Onyx Ahiakwo over 6 years ago in reply to Janar Plinkner

TI__Guru* 76230 points

Hi Janar,

The flag doesn't work. You shouldn't set it. Even if you set it, it doesn't interfere with the gauges functionality.

For the current scaling, you can trick the gauge by calibration say with 2A, but you tell the gauge it is 1A or 500mA depending on how much you want to scale by and then do the reverse calculation in your host.

Let me know if you have further questions.
Thanks
Onyx

0 Janar Plinkner over 6 years ago in reply to Onyx Ahiakwo

Prodigy 70 points

Hi Onyx,

That was the thing I wanted to know if it interferes with the gauges functionality, if it doesn't then that is good, I can set it to still indicate that there is scaling happening.

And yes from the presentation I know how to manually scale the gauge.

Janar

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BQ78350-R1: IPScale-ing not working, but does it affect in any way.