I'm evaluating the Renesas RX65N MCU EV Kit. In this post, I'm reviewing the Software Standby power save mode
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Software Standby Mode
This is a lower consumption mode than the Sleep mode in post 4a.
I'm doing the blogs a little out of order. There's a mode between Sleep and this mode. I learned that while writing the article.
source: Renesas datasheet
Measuring µA currents is a sensitive exercise. It should be done in a protected, stable environment.
In my setup, even if I move one arm in the direction of the circuit, the current ramped up with up to 300 µA.
I don't have a perfect lab, so I tried to get a stable measurement by
- leaving the gear on for an hour before starting the measurement,
- taking 2200 samples
- set the meter to a measurement that uses filtering (rolling 20) and only samples at 0-point crossings of the house electricity system..
- leave the room as soon as the sampling started and
- discarded the 200 first samples - enough time for me to be one floor down and nothing in the measure room.
Even in that situation, my measurements are just an indication of the current consumption.
The setup is similar than in the first blog. A µCurrent is used to translate the low current into a voltage. A DMM is then used to sample that voltage.
You can see the setup in the intro image. You have to translate the mV symbol into a mA symbol.
In the spreadsheet where I captured and processed the info (attached to this blog), I've adapted the chart to show the samples in µA.
The average current in Software Standby in my test is 465.235 µA.
The e2 studio project is also attached.