Verify working of DCDC converter on PCA10056

RE: Verify working of DCDC converter on PCA10056

Remco Poelstra — Mon, 28 Oct 2019 08:52:54 GMT

Thanks! That explains a lot.

RE: Verify working of DCDC converter on PCA10056

Stian Røed Hafskjold — Mon, 28 Oct 2019 07:14:28 GMT

Hi, in debug mode the PMU is not active, which means that the regulators are set to LDO mode (normal mode) and always powered on, even in idle or system off mode, and the clocks are always running. So this explains why you don't see the DCDC switching.

RE: Verify working of DCDC converter on PCA10056

Remco Poelstra — Fri, 25 Oct 2019 11:59:16 GMT

Hi, I'm using SES.

I noticed that my project also switches if I power cycle the board first. If I run directly from the debugger there is no switching.

So I believe there is nothing 'wrong' with the code, but more something related to the debugging connection.

Did you run in the debugger?

RE: Verify working of DCDC converter on PCA10056

Stian Røed Hafskjold — Fri, 25 Oct 2019 10:24:57 GMT

Can you post your hex file here, then I can try to compare. Also which project files did you use in the template folder? SES, IAR, Keil or GCC?

Maybe something went wrong with your SDK installation. Can you try to use a clean SDK?

RE: Verify working of DCDC converter on PCA10056

Remco Poelstra — Fri, 25 Oct 2019 09:48:35 GMT

Hi, Thanks for the HEX file. This is most interesting, as with your HEX file I see switching on L2. I re-tried my project and it doesn't cause switching.

I compared the binary files, but they are very different, so there isn't much information in there.

Can you advise on the next step?

RE: Verify working of DCDC converter on PCA10056

Stian Røed Hafskjold — Fri, 25 Oct 2019 08:31:35 GMT

Hi, sorry for the late reply. I tried your project and I can see the DCDC switching. I'm attaching the hex file, which we know is working, so you can try to out: devzone.nordicsemi.com/.../template_5F00_pca10056.hex

If you can't see any DCDC activity, I really don't know what is going on. If you want you can ship the DK to me so I can test it here in the lab.

RE: Verify working of DCDC converter on PCA10056

Remco Poelstra — Thu, 10 Oct 2019 07:34:47 GMT

If I enable DCDC0 (and set the board in high voltage mode), I do see switching on L4. I've still no clue why L2 doesn't show switching with DCDC1 enabled.

RE: Verify working of DCDC converter on PCA10056

Remco Poelstra — Wed, 09 Oct 2019 07:34:33 GMT

Can we exchange projects? I verified my code and measurement setup again and I truly do not see the pin switch.

Maybe there is a subtle difference in the code? I attached my code, please attach yours.

devzone.nordicsemi.com/.../template_5F00_project.zip

RE: Verify working of DCDC converter on PCA10056

Stian Røed Hafskjold — Tue, 08 Oct 2019 09:19:35 GMT

Running this code:

NRF_POWER->DCDCEN = 1;
for(;;){}

Measuring here with a 10x attenuation probe (PCA10056 v1.1.0):

The DCDC is turning on and off with an interval of 20us (the interval will change based on load):

And zooming in on the actual DCDC switching:

RE: Verify working of DCDC converter on PCA10056

Remco Poelstra — Thu, 03 Oct 2019 07:01:25 GMT

The sticker has the following numbers:

PCA10056

1.1.0

2019.9

683746617

RE: Verify working of DCDC converter on PCA10056

Stian Røed Hafskjold — Wed, 02 Oct 2019 14:56:07 GMT

What is the version of the DK?

RE: Verify working of DCDC converter on PCA10056

Remco Poelstra — Wed, 02 Oct 2019 14:18:11 GMT

A 70MHz scope, 1GS/s, horizontal set at 40ns/div.

This setting shows the 32MHz waveform of the HFXO nicely and it should be able to show a 8MHz waveform.

RE: Verify working of DCDC converter on PCA10056

Stian Røed Hafskjold — Wed, 02 Oct 2019 14:09:06 GMT

1.3V is the DC voltage of that pin both when DCDC is enabled and disabled.

What are you using to measure on DCC, and what is the sampling rate? The DCDC is switching at about 8MHz.

RE: Verify working of DCDC converter on PCA10056

Remco Poelstra — Wed, 02 Oct 2019 13:25:37 GMT

That does not start the DCDC converter. I also added NRF_CLOCK->TASKS_HFCLKSTART=1; before the for(;;) and that indeed enables the HFXO, yet still no switching.

As a side note, I do see about 1.3V on the pin.

RE: Verify working of DCDC converter on PCA10056

Stian Røed Hafskjold — Wed, 02 Oct 2019 13:06:14 GMT

Yes, a for(;;) will start the DCDC. Can you try with a main function that looks like this and nothing more?

NRF_POWER->DCDCEN = 1;
for(;;){}

RE: Verify working of DCDC converter on PCA10056

Remco Poelstra — Wed, 02 Oct 2019 11:58:21 GMT

Hi,

Unfortunately I don't currently have access to equipment that can actually measure the current consumption.

Hence, as a sanity check I just wanted to see the pin switch, knowing that I initialized it correctly.

When I place a for(;;) statement just before I start the FreeRTOS scheduler, I still do not see the pin switch.

Should that be sufficient power consumption for the SoC to use the DCDC converter?

RE: Verify working of DCDC converter on PCA10056

Stian Røed Hafskjold — Wed, 02 Oct 2019 11:22:32 GMT

When you enable the DCDC, it is is automatically controlled, always choosing the regulator that will consume the least current. When the chip is in IDLE the ultra low power regulator is used, and the DCDC is switched off.

Try to enable the DCDC and enable something that consumes current (Like the HF clock). Or prevent the CPU from sleeping in the main loop (removing any WFE/WFI calls), and you will see the switching on the DCC pin

An other way to see if the DCDC is enabled is to check the current consumption. Especially the radio TX/RX peaks will be different with DCDC enabled or not. Have a look at the online power profiler to see what's expected: https://devzone.nordicsemi.com/nordic/power