Patent ID: 8692609

Claim:
A method for sensing current, comprising: generating an alternating current (AC) voltage signal at an interconnected junction node of “N” cascode stacks, wherein the value of “N” is selected on the basis of defining a reference current that is “1/N” times the magnitude of an output current provided out of the interconnected junction node; generating the output current by coupling a proximal end of a load to the interconnected junction node and a distal end of the load to a ground node; generating the reference current in a replica circuit that includes a duplicate one of an upper leg or a lower leg of any one cascode stack amongst the “N” cascode stacks, the duplicate one of an upper leg or a lower leg automatically sourcing the reference current at “1/N” times the magnitude of the output current; coupling into a first input node of a comparator, the AC voltage signal generated at the interconnected junction node; coupling into a second input node of the comparator, a reference voltage signal that is generated by using the reference current that is generated by the replica circuit; and adjusting a controllable current source that is coupled to the replica circuit to set the reference voltage signal at a desired voltage level in order to compare the reference voltage signal to the AC voltage signal and generate therefrom, a current sense signal.