A low-voltage rail-to-rail CMOS V-I converter

This paper presents CMOS low-voltage rail-to-rail voltage-to-current (V-I) converters which could be used as basic building blocks to construct low-vo ltage current-mode analog very large stale integration (VLSI) circuits. In the circuit, an n-type V-I converter cell is connected in parallel with its p-type counterpart to achieve common-mode rail-to-rail operation. A linear differential relationship of the n-type V-I converter, or its p-type compl ement, is obtained using a new class-AB linearization technique. The consta nt transconductance value is obtained by manipulating the de bias currents of n- and p-type V-I converter cells. The circuit can operate from rail to rail with a power supply of 3 V or less, depending on the VLSI technology a nd the de bias current level.