CurrentSense is a tool for measuring current in embedded systems.
Description of the inputs:
- Power Supply: 3.3-6 volts that supplies power to the measurement circuitry.
- Optional Test Input: This input can be used to power the load under test. This is particularly useful for energy-harvesting or other systems where the input power is not stable.
- I_Sense: The measurable output signal that is proportional to current. To calculate current, divide the I_Sense signal (in volts) by the number that corresponds to the selected range value. This will return the current in amps.
- Range: Select the maximum current you want to measure. Select this as close to the maximum you wish to measure as possible.
- Load VCC Select: This selects how you would like to power the load under
test. The options
- Power Supply: Use the input from the power supply that is powering the measurement circuitry to also power the load.
- 3V3: Use the onboard regulated 3.3 V rail to power the load.
- Test Input: Use the external test input to power the load.
- To Load: Connect to VCC or the signal you wish to measure.
- GND: A set of ground pins for convenience.
The 300 mA range doesn't seem to work on v3.
You need a power selection jumper. You usually want to power the board externally, in which case you'll want the jumper in the high position as pictured.
- Connect external power (3.3-6V) to the EXT header at the top right. I usually also connect the external power to the GND header up here.
- Connect the power supply for your target to VIN header.
- Connect the VCC of your target to the VCC header
- Connect the GND of your target to the GND header. I usually connect target GND to the GND header at the bottom, whose label is occluded by the screw.
- Hook the scope probe to the test point at the top left (and GND anywhere)
The rest of the board is the same idea as above. Choose a range, measure voltage, divide by the number on the board, get amperage.