In a DC-to-DC converter, a current sense circuit and method generate a first current by a first transconductive amplifier responsive to the output current of the converter for a controller to switch a high side switch and a low side switch, a second current from a first voltage by a second transconductive amplifier, a second voltage from the second current by an adjustable resistor, and a bias signal from a difference between the second voltage and a third voltage by a bias apparatus to adjust the transconductances of the first and second transconductive amplifiers.