question about the power consumption of nRF52832 in BT connected and advertising mode

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

Stian Røed Hafskjold — Thu, 24 Jun 2021 11:21:18 GMT

Thanks for clarifying awneil

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

awneil — Thu, 24 Jun 2021 09:22:36 GMT

[quote userid="4556" url="~/f/nordic-q-a/76443/question-about-the-power-consumption-of-nrf52832-in-bt-connected-and-advertising-mode/316901#316901"]You typically don't need external pullups on the I2C, if you use the internal 13k pullups[/quote]

13K would typically be a bit high for a 3V I2C bus, surely?

[quote userid="104775" url="~/f/nordic-q-a/76443/question-about-the-power-consumption-of-nrf52832-in-bt-connected-and-advertising-mode/316874#316874"]if it still needs pullup resistor on i2c[/quote]

I2C always needs pullup resistors - that is fundamental to the bus operation.

The way to check if your value is OK is to look at the lines with an oscilloscope:

https://www.avrfreaks.net/comment/3074021#comment-3074021 - see the diagram & follow the link

Remember that the pullups will only ever draw current when the bus is in the low state; ie, during '0' bits of a bus communication. The bus idles high - so the pullups cause no current when idle.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

Stian Røed Hafskjold — Thu, 24 Jun 2021 08:58:54 GMT

You typically don't need external pullups on the I2C, if you use the internal 13k pullups

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

PYC — Thu, 24 Jun 2021 08:34:01 GMT

excuse me, we are debugging the power consumption in our application, the value of ours is higher than evaluation board, just to see is there any chance to save more power consumption.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

awneil — Thu, 24 Jun 2021 08:18:48 GMT

What does this have to do with the topic of this thread - "power consumption of nRF52832" ?

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

PYC — Thu, 24 Jun 2021 07:51:42 GMT

The I2C specification allows a line capacitance of 400 pF at most.
• The nRF52832 internal pullup has a fixed value of typ. 13 kOhm, see RPU in the GPIO chapter

->i checked the spec of nrf52832, saw the information as above. 52832 has internal pullup 13kohm, if program that to be I2C, do i need to do external pullup?

->if it still needs pullup resistor on i2c, what value of pullup is preferred?

thanks.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

Stian Røed Hafskjold — Wed, 23 Jun 2021 10:26:06 GMT

The internal and external clocks are used in two different ways, and not really comparable. The internal clock is started whenever it is needed by the peripherals automatically, e.g. the CPU. It has a very short startup time and cannot be controlled by the application. The external crystal has to be started manually, and will consume current after being started even though it's not actually being used. The startup time is a lot longer, and you will typically not use this unless you need the increased accuracy provided by the crystal, which in fact the radio does. If you just look at the run current for the CPU when running from the external crystal versus the internal clock, it's almost the same.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

awneil — Wed, 23 Jun 2021 10:14:09 GMT

it's not an option - as Stian Røed Hafskjold said, you need it for the radio to work.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

PYC — Wed, 23 Jun 2021 09:58:25 GMT

use external 32MHz crystal could be lower power consumption than use internal, is it correct?thanks.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

Stian Røed Hafskjold — Wed, 23 Jun 2021 09:23:11 GMT

You need an external 32MHz crystal to run the radio peripheral.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

PYC — Wed, 23 Jun 2021 03:46:58 GMT

Here is the quesiton on EE design, there is one crystal of 32Mhz on EVM board, could we save it, and disable it by internal setting? what is the impact if save the external crystal?

thanks.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

awneil — Tue, 22 Jun 2021 09:08:32 GMT

[quote userid="104775" url="~/f/nordic-q-a/76443/question-about-the-power-consumption-of-nrf52832-in-bt-connected-and-advertising-mode/316390#316390"]may i have your suggestion to modify the parameter to extend the battery life? [/quote]

Go on - in the online tool, you can just adjust the settings, and see what differences they make!

It's just a simple matter of moving the sliders, and clicking the buttons:

Once you've got a feel for what difference those settings make, you can think about how they impact on your applications performance.

As always, it's going to be a trade-off between performance & power consumption - only you know how that's going to fit with your applications requirements.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

Stian Røed Hafskjold — Tue, 22 Jun 2021 07:59:02 GMT

Sorry, I don't know anything about your application, so it's hard for me to give any suggestions. You can start out with the ble_app_pwr_profiling example in the SDK, it should compare well with the online power profiler. Use that to verify your measurement setup, custom HW, etc. Then add stuff one by one to figure out where it goes wrong.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

PYC — Tue, 22 Jun 2021 07:40:06 GMT

excuse me, may i have your suggestion to modify the parameter to extend the battery life? Thanks.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

PYC — Tue, 22 Jun 2021 00:52:20 GMT

yes, the supply voltage is 3V, may i have your suggestion to extend the battery life more?

Thanks in advance.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

Stian Røed Hafskjold — Mon, 21 Jun 2021 08:33:12 GMT

The file just contains the same default parameters as when you refresh the page. With these settings you can expect an average current consumption of 89 uA in advertising mode. This is very far from the 7.76mW (= 2.6 mA, assuming 3V input) reported consumption. So yes, there should be plenty of room for improvement here to extend the battery life.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

PYC — Mon, 21 Jun 2021 05:59:19 GMT

devzone.nordicsemi.com/.../opp_2D00_params_2D00_ble.zip

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

Stian Røed Hafskjold — Fri, 18 Jun 2021 12:07:51 GMT

Can you click on the "export settings" button in the Power Profiler and attach the file here, thanks.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

PYC — Thu, 17 Jun 2021 09:06:23 GMT

https://devzone.nordicsemi.com/nordic/power/w/opp/2/online-power-profiler-for-ble

excuse me, here is result by our setting, may you review it to see there is any setitng could improve the power consumption?

Thanks.

RE: question about the power consumption of nRF52832 in BT connected and advertising mode

awneil — Thu, 17 Jun 2021 06:53:50 GMT

It will depend very much on your settings - connection interval, advertising interval, etc ...

you can explore it with the online Power Profiler:

https://devzone.nordicsemi.com/nordic/power/w/opp