nRF9160 Low Power Example

[GNotman]

Hi,

I'm currently trying to evaluate the nRF9160 for one of our projects.

One key requirement is the power consumption when using eDRX.

I have tried profiling the at_client sample, but the lowest I've manged with the nRF9160DK is about 900uAs.

Additionally, the power profile does not seem to show the expected paging windows when eDRX is configured.

Is there any low power example, or documentation which can help me with this?

[GNotman]

Thank Håkon,

The lowest I have been able to see idle is with a modified version of the SPM example.

I'm using the nrf SDK v0.4.0 tag with a 0.8.2 DK, powered through P24 with SB44 cut.

The project has one configuration change Device Drivers->Serial Drivers has been unchecked.

Code has been modified with the following diff:

diff --git a/samples/nrf9160/spm/src/main.c b/samples/nrf9160/spm/src/main.c
index fa41616..f02e8fd 100644
--- a/samples/nrf9160/spm/src/main.c
+++ b/samples/nrf9160/spm/src/main.c
@@ -5,6 +5,7 @@
*/

#include <spm.h>
+#include <kernel.h>

/*
* Example code for a Secure Partition Manager application.
@@ -52,6 +53,7 @@

void main(void)
{
+ while(1) k_sleep(1000);
spm_config();
spm_jump();
}

Average current is 83.3uAs over a 30s sample.

I did get some direct support yesterday (after I created the above reply), which seems to indicate that I the issue is with using a 0.8.2 DK.

[GNotman]

Hi Håkon,

I've resolved the issue now.

The guide here helped me. https://devzone.nordicsemi.com/nordic/b/blog/posts/measuring-psm-idle-current-on-the-nrf91-dk

Edit: The guide seems to have moved. It can now be found here:

devzone.nordicsemi.com/.../measuring-psm-idle-current-on-the-nrf91-dk

(Note that for the 0.8.2 DK boards, it is SB44 that needs to be cut.)

I seems that if you removed the USB, the board will draw an additionally, 70-75uAs from the P24 header.

[Gordon Klaus]

What happened to this blog post?  It seems to have disappeared.

[GNotman]

They seem to have moved the post. 

I have updated the answer with the new link.

[RonanB96]

Did you get anywhere with disabling peripherals at runtime?