Fully Integrated Low-Ripple Switched-Capacitor DC–DC Converter with Parallel Low-Dropout Regulator

In this paper, we propose a fully integrated switched-capacitor DC–DC converter with low ripple and fast transient response for portable low-power electronic devices. The proposed converter reduces the output ripple by filtering the control ripple via combining a low-dropout regulator with...

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Bibliographic Details
Main Authors: Jeong-Yun Lee, Gwang-Sub Kim, Kwang-Il Oh, Donghyun Baek
Format: Article
Language:English
Published: MDPI AG 2019-01-01
Series:Electronics
Subjects:
Online Access:http://www.mdpi.com/2079-9292/8/1/98
Description
Summary:In this paper, we propose a fully integrated switched-capacitor DC–DC converter with low ripple and fast transient response for portable low-power electronic devices. The proposed converter reduces the output ripple by filtering the control ripple via combining a low-dropout regulator with a main switched-capacitor DC–DC converter with a four-bit digital capacitance modulation control. In addition, the four-phase interleaved technique applied to the main converter reduces the switching ripple. The proposed converter provides an output voltage ranging from 1.2 to 1.5 V from a 3.3 V supply. Its peak efficiency reaches 73% with ripple voltages below 55 mV over the entire output power range. The transient response time for a load current variation from 100 μA to 50 mA is measured to be 800 ns. Importantly, the converter chip, which is fabricated using 0.13 μm complementary metal–oxide–semiconductor (CMOS) technology, has a size of 2.04 mm2. We believe that our approach can contribute to advancements in power sources for applications such as wearable electronics and the Internet of Things.
ISSN:2079-9292