Current mirrors are frequently used in the signal path of an integrated circuit, for example, for differential to single-ended signal conversion within an operational amplifier. At low bias currents, the impedances in the circuit are high enough that the effect of frequency may be dominated by device and parasitic capacitances shunting the input and output nodes to ground, lowering the input and output impedances. The collector-base capacitance, formula_63, of Q3 is one component of that capacitive load. The collector of Q3 is the output node of the mirror and its base is the input node. When any current flows in formula_63, that current becomes an input to the mirror and the current is doubled at the output. Effectively the contribution from Q3 to the total output capacitance is formula_65. If the output of the Wilson mirror is connected to a relatively high impedance node, the voltage gain of the mirror may be high. In that case the input impedance of the mirror may be affected by the Miller Effect because of formula_63, although the low input impedance of the mirror mitigates this effect.