How to use P21 external supply in nRF52833 DK

[Ziyao Zhou]

Hi,

I am using nRF52833 DK and power it using P21 External supply. I connected P21 with the power profiler 2 and give 1.8V.  It works for serveral days, however, today I notice when I give 1.8V the program will not run. If I change to around 2.2V, it start running.

I have three questions:

1. What happen to the DK, before it can work under 1.8V, now it cannot.

2. When I am measure the current through P21, with all default setting(VDD power source, vEXT-nRF off, default), am I measuring the total current consume by the nrf52833 and interface MCU?

3.Can P21 use together with Lipo battery, if I connect a battery here, is there any battery management circuit after P21.

I have found some schemetic but I have no clue about what is happening in this DK. Thank you so much for your time!

[Simonr]

Hi

1. To power the nRF52833 from P21, you should slide the switch SW10 to the ON position and SW9 to the middle position (VDD).

2. This will only power the nRF52833 SoC, but please note that this is not the recommended way to measure current consumption. See section 5 of the DK user guide for information on how to do that. https://docs.nordicsemi.com/bundle/ug_nrf52833_dk/page/UG/dk/intro.html 

3. There is a separate connector for Li-Poly batteries on the nRF52833. This is the J6 or P27 that is designed for a Li-Poly battery source at 2.5-5V. If you're using it the SW9 pin should be set to the leftmost position (Li-Po).

Best regards,

Simon

[Ziyao Zhou]

Hi, thank you for your reply!

Simonr said:

1. To power the nRF52833 from P21, you should slide the switch SW10 to the ON position and SW9 to the middle position (VDD).

I notice when I switch SW9 tp ON, my code will not run, only when I put the thing default, my code will run.

Simonr said:

2. This will only power the nRF52833 SoC, but please note that this is not the recommended way to measure current consumption. See section 5 of the DK user guide for information on how to do that. https://docs.nordicsemi.com/bundle/ug_nrf52833_dk/page/UG/dk/intro.html 

What is the problem if I use the default setting (VDD power source, vEXT-nRF off) setting to power, will I have some noise or what.

Simonr said:

3. There is a separate connector for Li-Poly batteries on the nRF52833. This is the J6 or P27 that is designed for a Li-Poly battery source at 2.5-5V. If you're using it the SW9 pin should be set to the leftmost position (Li-Po).

I have accidently connect one battery in P21 and it works stably for a long peroiod. I want to know whether it will damage the DK if I keep using it