Low-voltage current operational amplifier with a very low current consumption

A 'digital' approach to the design of current operational amplifiers is introduced. Using CMOS inverters only, the layout of the resulting circuit can be designed exploiting standard digital cells libraries. An example current operational amplifier operating at a 2 V supply voltage and consuming a quiescent supply current less than 4.2 /spl mu/A, while maintaining an output current range of more than /spl plusmn/35 /spl mu/A, is presented. The performance of the circuit was verified by simulations on PSPICE.