Low voltage regulated cascode current mirrors suitable for sub-1V operation

A modified regulated cascode structure that incorporate a push-pull inverting amplifier and having a low output compliance voltage is used in the implementations of proposed current mirrors. P-SPICE simulations in 0.25μm CMOS technology validate the proposed current mirror structures at 1V. They offer very high output impedance about 30GΩ, consume around 200μW of power at 100μA d.c. current, and offer low output compliance voltage of 0.2V. The use of a level shifter across input transistor reduces the input compliance voltage to 0.25V, this also reduces current transfer range that has been significantly improved (14nA-318μA) and input compliance voltage has been further reduced to 0.14V, when adaptive bias is employed. The proposed LVCMs can operate with sub-1V single supply.