Originally posted by mr.clean
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It looks to me like you have your scope set to AC input coupling.
When you are measuring current draw from your battery, you need to have your scope set to 'DC' input coupling. Looking at the screen of your scope, it appears to be set to 'AC' input coupling (the sinewave symbol at the bottom). AC input coupling blocks DC, so your scope only sees AC. When measuring the current from the battery there will primarily be DC current plus any AC ripple on top of the DC input current. You therefore need to set your scope to DC coupling. You should pretty much always use a DC input coupling setting when making measurements as that shows everything (both DC and AC) that exists at the measurement point. Using AC input coupling is only for special cases where you want to block any DC component at the measurement point and only see any AC component that is there.
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