To measure the current draw of the MSPM0L2117 MCU using a multimeter, use the 3V3 jumper on the
J101 jumper isolation block. The current measured includes the target device, LaunchPad™ circuits, and
any current drawn through the BoosterPack™ plug-in module headers. To measure ultra-low power, follow these
steps:
- Remove the 3V3 jumper in the J14 isolation block,
and attach an ammeter across this jumper.
- Consider the effects that the backchannel UART
and any circuitry attached to the MSPM0L2117 can have on the
current draw. Consider disconnecting these at the isolation jumper block, or at least
consider the current sinking and sourcing capability in the final measurement.
- Make sure there are no floating inputs/outputs
(I/Os) on the MSPM0L2117. This causes unnecessary extra
current draw. Every I/O is either driven or, if the I/O is an input, is pulled or driven
to a high or low level.
- Begin target execution.
- For the most accurate current measurements, place
the device in free run mode and disconnect programming signals between the MSPM0L2117 and the debug portion of the board (header
J14).
- Measure the current. Keep in mind that if the current levels are fluctuating, then getting a stable measurement can be difficult. Measuring the quiescent states is easier.