Patent ID: 8610421

Claim:
A current generator, comprising: an op-amp having a first terminal that is arranged to receive an input voltage; a resistance selection circuit coupled to a second terminal of the op-amp and comprising a plurality of tunable resistors connected with each other; a resistor calibration circuit coupled to the plurality of tunable resistors; and at least one transistor, wherein a gate of the at least one transistor is coupled to an output of the op-amp, and a drain of the at least one transistor is coupled to the plurality of tunable resistors or a load, wherein the resistance selection circuit is configured to select at least one tunable resistor among the plurality of tunable resistors based on the input voltage, and wherein the resistor calibration circuit is configured to adjust a resistance setting of the selected at least one tunable resistor to control a current level of the current generator based on a power supply voltage or a current of a reference resistor.