5V power measurement PCA10040

RE: 5V power measurement PCA10040

Hugo — Wed, 29 Apr 2020 09:27:43 GMT

I measure (from the beginning) the current from the 5V power supply. That's what a SMU does :)
And the PCA10040 seeems to leak current, from Atmel processor (so sb29 cut), and from something else...

RE: 5V power measurement PCA10040

Simonr — Wed, 29 Apr 2020 05:26:07 GMT

[quote user="h2mille"]1.1mA is when SB9 is cut and P22 unplugged...so no current through the nrf.[/quote]

What are you measuring the current consumption over where the consumption is 1.1mA if it's not the nRF? What is drawing this 1.1mA? And if P22 is unplugged, where are you measuring the current from?

Best regards,

Simon

RE: 5V power measurement PCA10040

Hugo — Tue, 28 Apr 2020 11:03:02 GMT

can you explain me how you get so low current, while this example uses full time led?

RE: 5V power measurement PCA10040

Hugo — Tue, 28 Apr 2020 11:02:28 GMT

I meant SB9.
1.1mA is when SB9 is cut and P22 unplugged...so no current through the nrf.
when advertising, just one service every 8 seconds,

    init.advdata.name_type          = BLE_ADVDATA_FULL_NAME;
    init.advdata.include_appearance = false;
    init.advdata.flags              = BLE_GAP_ADV_FLAGS_LE_ONLY_LIMITED_DISC_MODE;

    init.srdata.uuids_complete.uuid_cnt = sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);
    init.srdata.uuids_complete.p_uuids  = m_adv_uuids;

    init.config.ble_adv_fast_enabled  = true;
    init.config.ble_adv_fast_interval = 64;//(in units of 0.625 ms, so 40ms)
    init.config.ble_adv_fast_timeout  = 6000;//60 seconds
    init.evt_handler = on_adv_evt;

RE: 5V power measurement PCA10040

Simonr — Tue, 28 Apr 2020 10:47:39 GMT

Hi Hugo

What do you mean about "P22 cut (no nRF52)"? If your application just advertises and not does much else I agree that 1.1mA still is too high.

What are your advertising parameters, etc.?

Best regards,

Simon

RE: 5V power measurement PCA10040

Hugo — Mon, 27 Apr 2020 19:29:07 GMT

ok, I did it, from a siglent SDM3055, on my application, during advertising I get 3.45mA usage on P22, I get 5mA on the SMU. So +45% energy lost, I don't know where. 3.45 still seems high for advertising (no led on), but still better. What do you think?
nb: my application use less power than your blink example, and as I vut more and more jumpers, I'd like to have a useful application left on it.
If I run with "P22" cut (no nrf52), I get around 1.1mA usage. Maybe SB10, but it still seems huge.
SB9 and SB29 are cut, measurement during led off.

RE: 5V power measurement PCA10040

Simonr — Mon, 27 Apr 2020 09:35:11 GMT

Hi Hugo

Sorry if I haven't been clear enough in my previous replies. In order to measure the current draw on the nRF52832 DK when powered from the 5V, please do the following steps:

Cut SB9 in order to enable the nRF current measurement pin header (P22). Keep in mind that P22 will need a jumper in order to reprogram the device when this SB is cut.
(Optional): Cut SB10 in order to bypass the reverse voltage protection diode on the USB power. See section 6.7.2 in the DK user guide for how to measure current using an oscilloscope.
(Optional): Cut SB29 in order to disable power for interface MCU.
Plug your current measurement tool onto the P22 header.
Power your device with a 5V source onto the 5V pin on P13.

This should be the required setup to measure the current consumption of the nRF52832 DK. This should not give you a current draw as high as 4.5mA, and if the graph is still as noisy as the one posted below, I think there's an issue in the setup either between the voltage source to the board or from the board to the current measurement tool.

Best regards,

Simon

RE: 5V power measurement PCA10040

Hugo — Fri, 24 Apr 2020 16:46:36 GMT

just to let you know I tested with a second pca10040, and with ADALM1000 board, and I have quite persistant data.
So it problem doesn't seems to be on my hardware. I'm missing something, but I don't know what, and I can't measure power used on pca10040 consistantly.
I also use for some IoT prototypes you board with some external arduino compliant battery shield, and I think I waste a lot of energy that I could save if I knew what waste so much energy on the board.

RE: 5V power measurement PCA10040

Hugo — Fri, 24 Apr 2020 11:00:00 GMT

on SDK15.3
as I said, the run app was the bt uart example (original, no modification).
I just tryed the blinky example, and the led is not blinky.
powering from:
5V pin: about 10mA quite constant (lazy to check the graph), including a led ON, not blinking. So I don't really trust your graph. Anyway, the led consumes about 5mA, we are still 5mA too high
VDD pin with 3.3V: 13mA... not sure it's the way to do it.
I don't know how to test the blinky app (and I don't really care), but i can see the device advert on my phone, so it seems to be well flashed.

Please, forget your board you want to sell me, and just tell we the way to measure power consumtion of only the nrf52chip+regulator through 5V line, with a SMU input.

RE: 5V power measurement PCA10040

Simonr — Fri, 24 Apr 2020 10:41:49 GMT

Hi Hugo

Indeed, these graphs look very noisy indeed. I assume the Y-axis' value is in Amperes, and if so it definitely looks very high. What application code are you running on the DK, is it one of our example projects or your own custom code? Here on my side, I have the following graph for the DK advertising regularly (ble_app_blinky).

Best regards,

Simon

RE: 5V power measurement PCA10040

Hugo — Thu, 23 Apr 2020 20:58:32 GMT

thanks. This is a new test from nordic uart exemple sdk15.3, 1st graph: advertising, 2nd graph: connected, sb29 cut, powered through 5V.
I think it's still far higher than what I should expect, it's nearly close to an Arduino x) . On the board shematics, there is a 300ma 3.3V AP7333-33SAG-7 regulator that shouldn't use so much current. So I'm missing something, but what?

ps: the power seems quite noisy, I don't know why, but I checked with a resistor and it's still well calibrated, no offset. It's missing some peak, as read frequency is 2ksample pr second, which doen't seems enough to see everything.

RE: 5V power measurement PCA10040

Simonr — Wed, 22 Apr 2020 13:30:33 GMT

Hi Hugo

Keep in mind that you can't supply the nRF52832 directly with 5V, as the maximum voltage rating is at 3.9V. Can you upload a picture or schematic of your test setup so I can get a clearer image? The DK/nRF is not connected to any peripherals what so ever, correct? Also, what application are you running on the nRF, is it one of our example projects or some custom code?

Best regards,

Simon

RE: 5V power measurement PCA10040

Hugo — Tue, 21 Apr 2020 11:37:03 GMT

I read already all these documents, but thank you for the advice.
I'm using Agilent 66309D+GPIB as a cheap but efficient SMU, but neither a scope, nor on ampermeter.
Also, I need to measure power from 5v to be able to include external devices, and the full system estimation connected to 150mA device which is out of your board scope, but compliant with my SMU.

I still have the same problem: how to power efficiently the board through 5V, without current leak?

RE: 5V power measurement PCA10040

Simonr — Tue, 21 Apr 2020 10:21:11 GMT

What measurement tool(s) are you using to measure the current on the DK? Have you checked out chapter 6.7 in the DK User guide which tells you how to measure the current consumption of either the whole board or the onboard chip? First of all, you should cut SB9, as P22 should be used to measure current consumption on the DK.

You can also check out the Power Profiler Kit which is made specifically for measuring current consumption on our nRF5 series and comes with a very thorough user guide and its own application in nRFConnect for Desktop.

Best regards,

Simon