Embodiments of the invention provide a current sensor. The current sensor comprises: a current sensing element having a first sensing terminal and a second sensing terminal, a first current mirror network CMN cell, a second CMN cell and a third CMN cell. The first CMN cell comprises: a first CMN that has a first high impedance terminal, a first low impedance terminal and a first output terminal, and a first local current mode feedback network LCMFN connected between the first output terminal and the first low impedance terminal. The first CMN cell is DC-coupled to the first sensing terminal of the current sensing element via the first high impedance terminal and operative to generate a first output signal according to the current sensed at the first sensing terminal. The second CMN cell comprises: a second CMN that has a second high impedance terminal, a second low impedance terminal and a second output terminal, and a second LCMFN connected between the second output terminal and the second low impedance terminal. The second CMN cell is DC-coupled to the second sensing terminal of the current sensing element via the second high impedance terminal and operative to generate a second output signal according to the current sensed at the second sensing terminal. The third CMN cell comprises: a third CMN that has a third high impedance terminal, a third low impedance terminal and a third output terminal, and a third LCMFN connected between the third output terminal and the third low impedance terminal. The third CMN cell receives the first output signal and the second output signal via the third high impedance terminal and the third low impedance terminal, respectively and is operative to generate a third output signal according to a combination of the first output signal and the second output signal.