Hello all. So i'm currently studying about current mirrors (specifically the Wilson current mirror). I'm reading "The Art of Electronics," page 89 (fig. 2.48 or the image attached). In there it says:
Ok so most of this makes sense to me, but shouldn't Q3 be the one "circumvented" from the Early effect since the load is attached to it?Q1 and Q2 are in the usual mirror configuration, but Q3 now keeps Q1's collector fixed at two diode drops below Vcc. That circumvents the Early effect in Q1, whose collector is now the programming terminal, with Q2 now sourcing the output current.
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