To measure the current draw of the MSPM0L1306 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 J101 isolation block, and attach an ammeter across this jumper.
- Consider the effect that the backchannel UART and
any circuitry attached to the MSPM0C1104 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 MSPM0C1104. 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 MSPM0L1306 and the debug portion of the board (header J101).
- 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.