Ublox EVK-NINA-B1, Руководство пользователя

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EVK-NINA-B1 - User guide
UBX-15028120 - R11 Product description Page 10 of 21
Figure 4: Power supply jumper positions of EVK-NINA-B1
1. To power the board from USB or external power supply, the jumper on J7 should be in position
1 as shown in Figure 4.
2. To power the board from the CR2032 coin cell battery for applications where NFC is not used,
the jumper on J7 should be in position 2.
3. To power the board from the CR2032 coin cell battery for applications where NFC will be used,
the jumper on J7 should be in position 3. The rationale for this is that the high field strength
on the NFC antenna can cause reverse current flow to the coin cell battery – hence the
possibility to connect the D4 diode as a protection for the reverse current.
If you would like to utilize the flexible input voltage 1.7-3.6 V of the NINA-B1 module, the power source
has to be connected to header J7. Connect the positive voltage to one of the pins - 1, 2 or 3 (bottom
row in Figure 4) and connect the ground to one of the two pins marked “GND” in Figure 4.
Coin cell battery considerations
When powering the EVK with a coin cell battery, keep in mind that the debug MCU will also have to be
powered by the battery. This will drain the battery faster than needed for a realistic solution. The
debug chip can be disabled to minimize the leakage during a battery powered setup. This is done by
removing resistor R9; R9 is shown in Figure 5.
Figure 5: Resistor R9
1.7.2 Disconnecting the debug MCU interface and LEDs
The J9 pin header includes all signals that are passed between the NINA-B1 module, the MCU
interface, and the LEDs.
If for some reason, you do not need these connections, then there is a possibility to disconnect these
signals separately by removing the selected jumpers. For instance, this could be useful in a current
measurement scenario.