Design of an OP-AMP Based on a LDO Regulator

An operational amplifier (OP-AMP) with a ground current of about 0.6μA is presented.Moreover,this amplifier reaps the benefits of incorporating a foldback current limiting circuit,which enables the low-dropout voltage regulator without the need of a special current limiting subblock.Therefore,the object of ultra-low power is realized because of a great reduction in transistors and current limbs.