BQ28Z620: Sense resistor

Shoo Saga

Intellectual 1456 points

Part Number: BQ28Z620

Hi Team,

What resister shows sense resistor value? I didn't find that kind of resister.

What are the difference between OCD and AOLD? OCD is programmable?

Thanks,

Shoo

10 months ago

0 Nick Richards 10 months ago

TI__Genius 10671 points

Hello Shoo,

When you say "resister", do you mean register? There is no register that contains the sense resistor
value. You will need to look at the schematic of your application to find the sense resistor value.
The sense resistor can be found between SRN and SRP.

The difference between AOLD and OCD is that OCD is controlled by the firmware while AOLD is controlled
by the analog front end.

Sincerely,
Nick Richards

0 Shoo Saga 10 months ago in reply to Nick Richards

TI__Intellectual 1456 points

Hello Nick,

Thank you for your reply. In the datasheet, ADC can measure ±100mV. and In TRM MIN/MAX OCC is ±32767mA. Which value is correct?

The datasheet recommend to use 1mΩ～3mΩ. this device support down to 0.5mΩ. Regarding to OCC value and ADC spec, this device can support up to 3 mΩ?

Thanks,

Shoo

0 Nick Richards 10 months ago in reply to Shoo Saga

TI__Genius 10671 points

Hello Shoo,

ADC measured voltage is completely different than the OCC. The ADC is for gauging, while OCC is a
protection.

Yes, the device can support up to 3 milliohm.

Sincerely,
Nick Richards

0 Shoo Saga 10 months ago in reply to Nick Richards

TI__Intellectual 1456 points

Hi Nick,

Thank you for your prompt reply.

So other component monitor OCC value except ADC?

Thanks,

Shoo

0 Nick Richards 10 months ago in reply to Shoo Saga

TI__Genius 10671 points

Hello Shoo,

I am a little confused by your questions?
What is your end goal of configuring this gauge?
For OCC, are you talking about the firmware side, or hardware side?

Sincerely,
Nick Richards

0 Nick Richards 10 months ago in reply to Nick Richards

TI__Genius 10671 points

Hello Shoo,

Forgot to add, I would recommend looking over this FAQ post that talks about the difference between hardware and firmware protections

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1111094/faq-what-are-the-differences-between-the-hardware-and-firmware-protections

Sincerely,

Nick Richards

Power management

Power management forum

BQ28Z620: Sense resistor