nRF7002 EK v1.0.0

Using an oscilloscope for current profile measurement

An oscilloscope can be used to measure both the average current over a given time interval and capture the current profile.

Make sure you have followed the instructions in Preparing the nRF7002 EK.
  1. Mount a 10 Ω resistor between the pins on P6.
  2. Connect an oscilloscope in differential mode or similar with two probes on the pins of the P6 connector as shown in Current measurement with an oscilloscope.
  3. Calculate or plot the instantaneous current from the voltage drop across the 10 Ω resistor by taking the difference of the voltages measured on the two probes. The voltage drop is proportional to the current. The 10 Ω resistor causes a 10 mV drop for each 1 mA drawn by the circuit being measured.

The plotted voltage drop can be used to calculate the current at a given point in time. The current can then be averaged or integrated to analyze current and energy consumption over a period.

Figure 1. Current measurement with an oscilloscope
nRF7002 EK current measurement with an oscilloscope

To reduce noise, you can do the following:

A minimum of one sample every 5 µs is needed to accurately measure the average current.