BQ34Z100-G1: BQ34Z100-R2 External temperature sensor configuration

Hi Enrico,

The Semitec 103AT is the thermistor on the EVM and can be used with the BQ34z100 pg21 linked below

bq34z100EVM Wide Range Impedance Track Enabled Battery Fuel Gauge (Rev. B) (ti.com)

What documentation made you skeptical?

Regards,

Diego

Hi Diego,

thanks for your answer. My question is if we can interface the BQ34Z100-R2 with a different external NTC: that is, is it possible to configure the polynomial coefficients (e.g. like with the BQ796942 front end)?

Or is the device locked to use a 10K NTC with B-value of 3435K (like the Semitec 103-AT)?

We're working on a custom design and we'd need to know if we can use different NTC or not. 

Thanks in advance,

E.

Hi E,

Sorry for the confusion, a different thermistor can be used. 

Attached is the .bqz with the thermal coefficients unlocked.

0100_2_02-bq34z100_tempcoef.bqzmodified BQZ disclaimer.pdf

Regards,

Diego

Hi Diego,

sorry but how can I calculate the coefficients?

Can you share the right tool for this?

Within this post a wrong spreadshhet is shared:

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1113208/bq34110-need-the-temperature-coefficient-calculator-for-bq34110

The one shared with SLUA398 does not fit too.

I suppose a common model for BQ34110 and BQ34Z100 is used, but the right tool is needed:

Many thanks,

Enrico

Hi Diego,

attached the data file and NTC datasheet (data has been also used for GPC tool for BQ769x2 front end).

The exact P/N is Vishay NTCLE413 10K 3 % B3984 K:

May I ask you to share the spreadsheet for the calculation?

Why TI does not public this tool and keep the temperature model customization through the E2E forum?

Thanks in advance for the support,

best regards,

E.

ntcle413.pdfThermistor files for GPC-update.zip

Hello,

Today is a national holiday. We will get back to you later this week.

Regards,

BMS Apps Team

Hi,

The Semitec 103AT, is the thermistor that is intended to be used with the gauge.

The thermistor coefficients are private parameters; therefore the tool is private.

Please use the coefficients below.

a1 -20447

a2 35167

a3 -27444

a4 30497

a5 463

b1 -197

b2 383

b3 -3200

b4 4926

Regards,

Diego

Hi Diego,

the temperature model is based on four coefficients and minimum AD value. It's not the model with a_n and b_n coefficients:

Thanks,

E.

Hi E,

Sorry about that, I forgot this is an older device and the coef are calculated differently.

Please allow me some time to calculate the coef for the BQ34z100

Regards,

Diego