BQ40Z50EVM-561: no change in the RSOC while attempting to charge

Steven Corrales

Part Number: BQ40Z50EVM-561
Other Parts Discussed in Thread: BQSTUDIO, BQ4050EVM-561

Hello,

I am attempting to test the BQ40z50evm-561 using the BQ studio. I am attempting to run a charge and discharge simulation. I have connected the Pack+ and the Pack- to the charger. I have removed the SYS PRES to Pack- wire as i have set the NR bit in the DF configuration. I first attempted to charge the battery pack by FET_EN=1. Since that process did not work i continued by setting CHG_TEST=1 and DSG_TEST=1. This also did not charge my battery pack. The pack i am testing (INR18650-30Q) came with a stock fuel-gauge and so ran another test by attempting to charge the pack through their connection but still attempting to read the bq40z50EVM. As the pack charged the RSOC did not change from 16% nor did the remaining capacity change as the battery voltage continued to rise.

If anyone has any idea as to why this kind of issue is happening, i would appreciate the help

Thank You,

Steven

over 8 years ago

0 Onyx Ahiakwo over 8 years ago

TI__Guru* 76230 points

Hi Steven,

Can you send a screen shot of bqstudio after you started it.

Also, you need to make sure the charge and discharge fets are turned on by sending the fet enable command, and make sure that no safety feature had triggered that would turn off the fets. You need to make sure IT enable command has been sent and that the QEN flag is set. You will also need to perform a learning cycle to make sure the gauge learned the qmax and resistance of the battery to be able to report SOC correctly

thanks

Onyx

0 Steven Corrales over 8 years ago in reply to Onyx Ahiakwo

Prodigy 100 points

hello Oxyn,

Ive seen in the older software that there is a way to implement the learn cycle, how would i go ahead and be able to do such a thing. Below is also a scream shot of my bq.

0 Onyx Ahiakwo over 8 years ago in reply to Steven Corrales

TI__Guru* 76230 points

Hi Steven,
It appears you may have not completed a successful learning cycle. Pls follow the app note below to complete the learning cycle on this device.
www.ti.com/.../getliterature.tsp
thanks
Onyx

0 Steven Corrales over 8 years ago in reply to Onyx Ahiakwo

Prodigy 100 points

Hi Onyx,

I'm running through the lifecycle test now.. Only thing is that i am still charging and discharging through the battery packs stock fuel gauge. For some reason even if the FETs are enabled the bq40z50EVM isnt allowing me to charge and discharge

Steven

0 Onyx Ahiakwo over 8 years ago in reply to Steven Corrales

TI__Guru* 76230 points

Hi Steven

Your screen shot shows the charge and discharge fets are enabled. Can you measure the voltage on the gates of the fets to ensure that there is sufficient voltage to turn them on? That is the only reason i can think of that will prevent charging and discharging through the fets of your board.

thanks

Onyx

0 Steven Corrales over 8 years ago in reply to Onyx Ahiakwo

Prodigy 100 points

Both gates voltage are equal to the BAT voltage. I have the PACK+ connected to Charger+ and Pack- connected to Charger- . Nothing happens when connected to a charger. Is the Fuse-blowing circuit relavent to this and should i have cut the copper for this test as it states in the User manual?

0 Onyx Ahiakwo over 8 years ago in reply to Steven Corrales

TI__Guru* 76230 points

hi Steven

If the fets are turned on, both gates are supposed to be about 9V higher than the bat voltage and not the same voltage as BAT. pls check your set up followed what is described in the EVM user guide. Btw , are you using our EVM or your own board? and No, the fuse blowing circuit isn't relevant to this.

Also, Send your srec so we test out on our board to see if it is a problem with your setting.

thanks
Onyx

0 Steven Corrales over 8 years ago in reply to Onyx Ahiakwo

Prodigy 100 points

bqevm.zipI am using your board in parallel with my board because the BQ wont allow me to charge or discharge

0 ThomasCosby over 8 years ago in reply to Steven Corrales

TI__Guru 73830 points

I tested your srec and the charge pumps on the CHG and DSG FETs is working properly. The CHG and DSG pins are about 11V higher than BAT. There must be a hardware problem with your setup.

0 Steven Corrales over 8 years ago in reply to ThomasCosby

Prodigy 100 points

The box that my gauge was shipped in was Labeled BQ40z50evm-561 but my actual board says BQ4050evm-561. Would that be the issue?

0 Onyx Ahiakwo over 8 years ago in reply to Steven Corrales

TI__Guru* 76230 points

Hi Steven,
Those are two different devices. I suggest you contact our customer service for them to get you the correct board. Sorry for the trouble.
thanks
Onyx

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BQ40Z50EVM-561: no change in the RSOC while attempting to charge