A LDO with open-loop gain compensation tracking load-current and output capacitor-less

This paper presents a low dropout (LDO) linear regulator with load current tracking open-loop gain compensation and the output is stable without an external bypass capacitor. After a general error amplifier, follows a buffer stage to drive the gate of pass device. Buffer stage tracks the variation of load current to change the bias current of error amplifier to achieve the open-loop gain compensation. After a general theoretical analysis that takes into account the loop stability, confirming the feasibility of proposed LDO. Simulation results implemented in 0.5 um BCD process which validate the methodology are also included at the end of this paper.

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