You're getting them confused. tDCS is measured in 1-4 milliamps in usually 10-30 min durations. 2 milliamps is considered optimal and it can get dangerous when you reach 4 milliamps or above. Darpa has done extensive research in enhanced learning using tDCS.
Not confused at all; that’s why I specified tDCS, idiot. Max 2 ma. Trained as neuroscientist.