nRF52832, nRF5340 current consumption comparison

[John Lee]

It is an extension of the ticket below.
devzone.nordicsemi.com/.../nrf5340-current-consumption-issues
I'd like to find out what causes the huge difference in current consumption on the two boards.

An online power profiler (OPP) was used to estimate the radio current, and PPK2 was used to measure the actual current consumption of the board.

<52832>




OPP: 77uA
Measurements: 72.23 uA
Measurement_base: 3.04 uA

<5340>




OPP: 56uA
Measurements: 85.87 uA
Measurement_base: 6.76 uA

OPP simulations suggest that the 5340 will have lower current consumption, but measurements do not.
Comparing the currents over one connection interval clearly shows the difference. Both radio/idle the 5340 has high current consumption.

<52832>



Interval (60 ms): 70.28 uA
Peak (5 ms): 809.6 uA
Base (55 ms): 3.06 uA

<5340>



Interval: 78.53 uA
Peak: 870.45 uA
Base: 6.54 uA

I'd like to know where this difference comes from.
Is it simply because the 5340 has two cores?
52832, IDDFLASHCACHEDCDC: 3.7 mA
5340, IAPPCPU3 + INETCPU2: 3.6 mA + 2.6 mA = 6.2 mA

I tried to compare the current consumption of the two mcu peripherals in the datasheet, but the 5340 doesn't provide enough information. (gpiote, pof...)
I want to make sure I've achieved sufficient current optimization.

[Simonr]

Hi

By "the Nordic blog" I assume you refer to the optimizing power on nRF5340 SoC designs guide, correct? In your config file I see that CONFIG_SERIAL is set to Y, which is a common cause for increased current consumption as it is part of the configs required to use serial logging. Try disabling this to make sure logging is properly disabled to see if that affects the current consumption on the nRF5340. Other than that I didn't spot anything on first glance that should be causing this.

Also make sure all unused peripherals are disabled on both the APP and NET core in your nRF5340 project. This can be done with the DeviceTree GUI in the VS code nRF Connect extension for example, where you get an overview of what processes/peripherals are enabled in a specific project and makes it easy to see what's enabled and not.

Best regards,

Simon

[John Lee]

Yes, I configured power optimization by referring to that blog.

I have configured CONFIG_SERIAL=y, CONFIG_UART_ASYNC_API=y only for app core because my project contains uart serial communication.

Disabled all peripherals not used by the app and net core.

John Lee said:

Is it possible with the 5340 to achieve the same level of power consumption as the 52832?
I need to check if it consumes higher power because of the physical (electrical) characteristics of the MCU or if there is an optimization that I did not apply.

Can you answer the above question?

Simonr said:

Other than that I didn't spot anything on first glance that should be causing this.

If so, I'll conclude that I've achieved maximum optimization.