An Integrated LDO Regulator for Self-powered Systems
In the contemporary energy-efficient integrated systems the demand for on-chip power management units like regulators has significantly increased. The voltages provided by alternative power sources are transmitted towards the power conversion subsystem. The main purpose for such subsystems is to stabilize the voltage level to meet the demands of the energy customers: digital logic blocks or IP-blocks. The reason for LDO regulator is to reject the power supply ripples from power management circuit. In this paper, the features of LDO operation and design formulas are observed with regard to regulator unit as a part of the self-powered design. During the LDO design process it is strongly recommended to perform analysis of static and dynamic characteristics, to verify the feedback loop parameters and agree on the way of compensation type. As a part of the research activity we proposed the LDO with as much as 100uA quiescent current consumption and obtained the static characteristics. The low-voltage circuit solutions were used and good PSRR values at relatively high frequencies was achieved for entire design.