NuMaker-LoRaD470/868/915-M252
Dec. 21, 2020
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3.6
External Reference Voltage Connector
Table 3-17 presents the external reference voltage connector.
Connector
Description
VREF1
Connector for user to connect to the external reference voltage pin of the
target chip. User needs to remove the L5 ferrite bead.
Table 3-14 External Reference Voltage Connector
3.7
Voltage Adjustable Interface (VAI) Connector
Table 3-15 presents the voltage adjustable interface connector.
Connector
Description
VDDIO
Connector for user to easily connect to the V
DDIO
pin of the target chip as
power source of PA.0 ~ PA.5. User needs to remove the R15 resistor.
Table 3-15 Voltage Adjustable Interface Connector
3.8
Battery Voltage (V
BAT
) Connector
Table 3-15 presents the battery voltage interface connector.
Connector
Description
VBAT
Connector for user to easily connect to the V
BAT
pin of the target chip as
power source of PF.4 ~ PF.6, RTC and LXT. User needs to remove the
R17 resistor.
Table 3-16 Battery Voltage Interface Connector
3.9
Ammeter Connector
Table 3-17 presents the ammeter connector.
Connector
Description
AMMETER
Connector for user to measure the target chip power consumption easily.
User needs to remove the R16 resistor.
Table 3-17 Ammeter Connector
