How to use nRF52840-DK with an external power supply?

[eye]

Hello,

Now,in my application I use to power the nRF52840 with a 3.3V external supply at the VDD pin.

I want to know how to set it, I want to power the nRF52840 with a 3.3V external supply at P21.

It does not energize in this setting.
Is there a missing or unnecessary settings?

・SB36 -> shorted
・SB39 -> shorted
・SW6 -> DEFUULT
・SW8 -> ON
・SW10 -> OFF

Best Regard.

eye

[Jared]

Hi,

How is SW9 configured?

Best regards

Jared 

[eye]

Hi,Jared

Thank you for reply

  SW9 =>VDD

Best regards

eye

[eye]

PCA10056 version
v 1.0.0
2018.51
683100802

[Jared]

Could you try changing the SB39 and SB36 to its default position of open. And then connect the external supply to P21. What voltage do you measure on the VDD pinout on the DK? Make sure that you only connect the external supply and no other power source. 

[eye]

We got new board. and confirmed.

There seems to be no problem in conclusion.

Factory default board, Available with an external power supply.

But When it’s execute Github’s demo program, the same things happened.

Is this program not available with external power supply?

https://github.com/NordicPlayground/nrf52-ble-image-transfer-demo/tree/master/pca10056

Remarks) I made that correction ,for SDK version is v15.3.0.

[Jared]

Hi,

The ble image transfer demo shouldn't be dependent on the power supply.

• Could you be more specific of what happens you execute the Github demo program?
• Do you measure any voltage on the VDD pin?
• What IDE are you using to program the chip?

Best regards

Jared

[eye]

Hi,

I have two boards, so I will organize them once.

[Settings with differences]

• Board_A
  ・circuit :SB40 ->cut , P22 -> shorted
  (I was trying to use for comparison of voltage.I used it when I asked a question)
•  Board_B
  ・circuit :default. it's not modified at all
  (New! I prepared to compare the action)

[Common settings]

• IDE: SEGGER Embedded Studio for ARM 4.16
• SDK:nRF5 SDK ver15.3
• program: nrf52-ble-image-transfer-demo
  => The code has been modified by the SDK version upgrade.
  (nrfx_power_clock.c -> nrfx_power.c)
• Camera: Arducam Mini 2MP camera module (OV2640)
• Camera's Wiring: I reference GitHub's readme.

-------

Q1) Could you be more specific of what happens you execute the Github demo program?
A1) Board_A and Board_B do the same action

 [OK] VIN3-5V(3.3V)  / J2.USB connector(5V)

1. Energize at 220mA.
2. LED_1 Keep on flashing.
3. Android_App can scan Board with BLE5.
4. Android_App can connect Board with BLE5.
5. Android_App can take camera's pictures and stream.

[NG] P21.eternal supply(3.3V) / Coin cell battery(3.0V)
=>  Do not energize

--

Q2) Do you measure any voltage on the VDD pin?
=> No. Board_B's circuit has not been modified at all.

However, when measuring the voltage on the Board_A, it is the same as the A1.

--
Q3) What IDE are you using to program the chip?
A3) SEGGER Embedded Studio for ARM 4.16

Best Regards.

eye

[eye]

I checked additionally

 P27.Li-in connector(3.3V) 

=>  OK

I think so, It is effective only when using 5 V power sources.

eye

[Jared]

Hi,

What power source are you using when it's not working? 

eye said:

 P27.Li-in connector(3.3V) 

=>  OK

Does this mean that it worked with the Li-Po battery connected to P27?

Best regards

Jared