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Digital vs Analog Low Dropout Regulators a Comparative Study

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Digital Technologies and Applications (ICDTA 2023)

Part of the book series: Lecture Notes in Networks and Systems ((LNNS,volume 669))

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Abstract

Multiple integrated power regulators with compact size, process extensibility, and low voltage supply are required for an energy efficient system on chip (SoC). Traditional analog low-dropout regulators (ALDOs) may barely achieve all these necessities when digital LDOs (DLDOs) are suitable solutions. The power-speed trade-off, however, limits the naturally slow transient response of the typical DLDO with synchronous control DLDOs, and fully turned-on power switches may lead to power supply ripples, resulting in poor power supply rejection (PSR). In this paper, a comparative study between ALDOs and DLDOs is presented. We first generally weigh the advantages and disadvantages of ALDOs and DLDOs. The latest DLDO strategies for quick transient response and PSR improvement are briefly discussed next. Finally, we discuss current design trends and potential DLO developments.

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Authors and Affiliations

  1. Laboratory of Computer Science and Interdisciplinary Physics (LIPI), Normal Superior School Fez Sidi Mohamed Ben Abdellah University, Fez, Morocco

    Said El Mouzouade, Karim El Khadiri & Ahmed Tahiri

  2. Laboratory of Computer Science, Signals, Automation and Cognitivism (LISAC), Department of Physics, Faculty of Sciences Dhar El Mahraz, Sidi Mohamed Ben Abdellah University, Fez, Morocco

    Hassan Qjidaa

  3. Systems and Sustainable Environment Laboratory (SED), Faculty of Engineering Sciences (FSI) Private University of Fez (UPF), Fez, Morocco

    Mouhammed Ouazzani Jamil

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  1. Said El Mouzouade
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  2. Karim El Khadiri
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  3. Hassan Qjidaa
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  4. Mouhammed Ouazzani Jamil
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  5. Ahmed Tahiri
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Correspondence to Karim El Khadiri .

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Editors and Affiliations

  1. Ecole Nationale des Sciences Appliquées, Fez, Morocco

    Saad Motahhir

  2. Faculty of Sciences, Sidi Mohamed Ben Abdellah University, Fez, Morocco

    Badre Bossoufi

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El Mouzouade, S., El Khadiri, K., Qjidaa, H., Jamil, M.O., Tahiri, A. (2023). Digital vs Analog Low Dropout Regulators a Comparative Study. In: Motahhir, S., Bossoufi, B. (eds) Digital Technologies and Applications. ICDTA 2023. Lecture Notes in Networks and Systems, vol 669. Springer, Cham. https://doi.org/10.1007/978-3-031-29860-8_77

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