A nested transimpedance amplifier (TIA) circuit comprises a zero-order TIA
having an input and an output. A first operational amplifier (opamp) has
an output and an input that communicates with said output of said
zero-order TIA. A first power supply input applies a first voltage to the
zero-order TIA. A second power supply input receives a second voltage. A
charge pump module develops a third voltage based on the first voltage
and the second voltage, wherein the third voltage is applied to the
opamp.