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Measuring wide range current draw of micropower applications
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magic:

--- Quote from: splin on October 31, 2019, 11:36:48 pm ---But make sure you clamp the high gain amp to prevent it saturating if the overdrive recovery time could seriously impact the accuracy. ([EDIT 3] For example, the 2MHz auto-zero MCP6V26 has a recovery time of around 50us). How big a problem that is depends on the threshold level where the high gain range becomes active and the frequency that the range changes. In cases, such as IOT applications, where an MCU spends much of its time, op-amp saturation wouldn't be much of a problem as the recovery time is insignificant compared to the total time spent in sleep mode.

--- End quote ---
For this application, low current range bandwidth is sub-1Hz and high current events occur extremely rarely. The MCU could sample the high current channel at 100kHz or so to catch wakeups reliably and only probe the low current channel once per a few seconds and discard the sample when a high current event has been registered within its vicinity.
Just the lowest possible effort to get this particular measurement done and forget about it.
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