A charge pump circuit comprising an operational amplifier having a first input (+) and a second input (-) and an output, a feedback loop including reactance means coupled between the output and second input,
   a first current source providing a first current to a first resistance (R) which is coupled to said first input,
   a second current source providing a second current equal to said first current, first npn transistor switch means (Q6) for selectively switching said second current to said second input,
   a second resistance (R') equal in value to said first resistance coupled to said second input and second npn transistor switch means (Q3) for selectively switching a third current equal and opposite to said first current via said second resistance to said second input,
   whereby said reactance means is charge pumped by said second and third currents.