The average current drawn by the nRF52840 System on Chip (SoC) can be measured using an ampere meter. This method monitors the current in series with the nRF device. A true Root Mean Square (RMS) ampere meter is recommended.
To measure the average current drawn by the nRF52840 SoC perform the following steps.
- Prepare the Development Kit (DK) as described in Set up the development kit.
- Connect an ampere meter between the pins of connector P22 as shown in the following figure.
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Do one of the following:
- Ensure that the SoC is in a state where it draws a constant current.
- Ensure that the activity on the device changing load current, such as Bluetooth LE connection events, is repeated continuously and has a short cycle time of less than 100 ms so that the ampere meter averages complete load cycles and not parts of the cycle.
- Set the average timing of the ampere meter to a long interval, such as 1 s or longer.
- Set the dynamic range of the ampere meter between 1 µA and 15 mA, so that it is wide enough to provide accurate measurements.
Figure 1. Current measurement with an ampere meter
