Zoe-M8B V_Bckp Current; Zoe-M8B Optional Flash And Logic Current - u-blox EVK-M8BZOE User Manual

6.1.2 ZOE-M8B V_BCKP current

To measure the backup current consumption for V_BCKP of ZOE-M8B follow the below steps, a picture of the
setup can be seen at Figure 10:
1. Connect a voltmeter to J6 pin 1 and pin 2 to see the voltage over the 100 Ω current measurement shunt
resistor in the V_BCKP supply.
2. Disconnect the main supply.
3. Read the voltage on the voltmeter and convert to current. 1 mV equals 10 uA.
See Figure 10 for an example where 0.0016 V is measured by multimeter over 100 Ω V_BCKP shunt resistor. This
corresponds (1 mV equals 10 uA) to 16 uA backup current.
Figure 10: Setup to measure the V_BCKP current consumption of ZOE-M8B on EVK-M8BZOE

6.1.3 ZOE-M8B optional Flash and logic current

If the optional Flash is used e.g. for logging purposes, the current consumption of that can be measured using J4;
see schematic in section 8.
UBX-17053592 - R03 Early Production Information
EVK-M8BZOE User Guide
Measuring current consumption
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