You would usually use a circuit, something like this (with a normal transistor):
But Darlingtons are more complicated, because their gains are usually considerably higher, they can have resistors inside (I think yours have resistors), which need to be overcome.
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I think one of yours looks like this:
As already discussed above, in other posts. It probably has a (parasitic) diode between the collector and emitter. The application note (see link in one of my earlier posts), seems to say that the process of adding the resistor(s), to the darling transistor, also creates the parasitic diode. Because of how they are made.