Frequency compensation techniques for op-amps and LDOs: A tutorial overview

Today's op-amp is not just a stand-alone IC, rather it is more custom and complex, catering the needs of highly integrated SoC. Tighter line and load regulation, low quiescent current operation, capacitor-free and wide-range output capacitor specifications are some of the contradicting requirements in an LDO, which drive newer topologies and newer frequency compensation techniques. The objective of this paper is to provide a tutorial treatment of some of the basics and recent advances in frequency compensation. Transistor level implementation of efficient LHP zero techniques and design examples are detailed.

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