NRF52840-MICRO BOARD
Things to note
1. The NFC function cannot be enabled when using 5V to power VDDH, which means that the NFC function must be powered by 3.3V through vdd_nrf.
2. The chip must be powered by Vbus before the USB of the chip can be used. Cutting off vbus when powered by battery can save power.
3. The lower part of the ceramic antenna must be clear.
4. If you do not need to use the bottom IO, you can directly solder the side half hole and ignore the bottom pad.
5. When using 5V power supply, just supply power to VDDH, please ignore vdd_nrf.
6. USB D+ and D- do not need to be connected with 22 ohm resistors.
7. If you have the conditions and have high requirements for stability, please connect a transient suppression diode to the positive and negative poles of the power inlet and D+ D-.
8. There are four IOs that are not led out, namely P0.04 P0.26 P0.31 P1.15
9. Please check the package and schematic diagram directly for all GPIO name divisions.
10 size is 18.45mm*14mm, please refer to the DXF file for details
NRF52840-MICRO BOARD DOC&SCH&Package library