PPK questions

RE: PPK questions

eyss5 — Tue, 16 Jun 2020 05:11:21 GMT

Not that I know of. I've only used the PPK with the nRF52DK connected to USB. I'll keep checking, thanks.

RE: PPK questions

Jared — Mon, 15 Jun 2020 08:37:32 GMT

Well, i'm suspecting based on your result that the ppk might be damaged? Have you used it outside of it's operating conditions? Note, that the PPK only supports a current draw up to 70 mA, anything over this can actually damage it.

RE: PPK questions

eyss5 — Sun, 14 Jun 2020 04:28:25 GMT

Jared or others -- any thoughts on the negative current? Thanks.

RE: PPK questions

eyss5 — Fri, 12 Jun 2020 07:14:23 GMT

Yes, I just flashed ble_app_uart_pca10040_s132 from a completely fresh nRF5SDK16. It reads 2.26mA when scanning and -0.24uA after 180s timeout and goes to sleep.

I have SW9 open and SB11 disconnected on the nRF52DK.

On the Power Profiler app, when the radio is not running the baseline current is 1.9mA and the overall average is 2.26mA, so it's consuming 336uA during radio transmission, which looks exactly right compared to the online power profiler.

Now I need to figure out why the baseline current is 1.9mA and if that's even a correct reading. And also the -0.24uA during sleep. The other posts make it seem like a setup issue with current leakage.

edit: Ok, looks like UART consumes quite a bit of current. so that might be it. Still no answer on the negative current though. It'd be good to figure that one out so I can trust the readings that I'm seeing.

RE: PPK questions

Jared — Fri, 12 Jun 2020 06:49:53 GMT

Correct
If you get negative current then I suggest redoing the measurement as it's not correct. Are you measuring with the unmodified ble_app_uart_peripheral example?

RE: PPK questions

eyss5 — Fri, 12 Jun 2020 05:41:24 GMT

Hi Jared,

Looks like I mis-read the silkscreen for SW3 as "COM" in my post above. My current understanding of SW3:

DK: J-link programs the PPK above

EXT: J-link programs the nRF52 DK below

I find that I need to put the switch back to DK when I open the Power Profiler, otherwise it seems to overwrite my nRF52DK firmware, is that correct? Anyway, I'm now able to get the firmware to the correct places, so thanks for that.

Also, can you comment on my question #2 above (negative current)? The readings on the peripheral are still the same: 2mA (when scanning) and -0.1uA when sleep. Should SW9 = open?

RE: PPK questions

Jared — Thu, 11 Jun 2020 13:46:45 GMT

Hi,

Make sure that switch 3 is set to DK. It will program the nRF52 DK instead of the PPK if it's set to EXT. The nRF Connect Power Profiler app will reprogram the PPK if it's not already programmed with the correct FW.

regards

Jared