Browsing by Author "Lin, Moris"

Now showing 1 - 5 of 5

A 0.6 V Resistance-Locked Loop Embedded Digital Low Dropout Regulator in 40 nm CMOS With 80.5% Power Supply Rejection Improvement
(2015-01-01)
Chiu, Chao-Chang
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Huang, Po-Hsien
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Lin, Moris
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Chen, Ke-Horng
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Lin, Ying-Hsi
The proposed resistance-locked loop (RLL) can achieve high PSRR of -16 dB digital low dropout (DLDO) regulator without consuming much power which is the drawback in prior arts. Even at light loads, the RLL can be shut down for power saving. Furthermore, the duty compensator ensures DLDO stability under different duty ratio of supply voltage. The operation voltage of proposed DLDO can be down to 0.6 V and the peak current efficiency is 99.99%. The test chip was fabricated in 40 nm CMOS process with all the transistors implemented by core device for small silicon area.
Adaptive Pulse Skipping and Adaptive Compensation Capacitance Techniques in Current-Mode Buck-Boost DC-DC Converters for Fast Transient
(2013-01-01)
Ehrhart, Andreas
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Lin, Moris
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Huang, Yung-Sheng
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Lee, Yu-Huei
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Chen, Ke-Horng
to have a good power management especially for portable devices it is necessary to use the whole battery voltage range (e. g. of Lithium-ion batteries), to provide a fixed output voltage of for example 3V. In this paper a fast transient (FT) current mode buck-boost DC-DC converter with adaptive pulse skipping (APS) and adaptive compensation capacitance (ACC) is proposed. The buck-boost DC-DC converter can work in three different modes, buck, boost and buck-boost. It cannot only use the whole battery range from 2.7V to 4.2V, but also has a good response time with a low voltage undershoot/overshoot at load current variations, due to the APS and the ACC. With the proposed fast transient techniques, improvements could be made in the voltage overshoot/undershoot and the response time. In boost mode, the improvements, in the voltage undershoot and the response time from light-to-heavy load (100mA to 500mA), are 16.7% and 58.8%, respectively. In buck mode, 40% and 49.2% and in buck-boost mode, it is 10% and 63.9%. In case of a load variation from heavy-to-light load (500mA to 100mA), similar results could be reached in every operation mode. The proposed DC-DC buck-boost converter realizes a good power management and a good transient performance to generate a stable supply voltage for portable devices. Its working frequency is 1MHz.
Authentic Mode-Toggled Detector with Fast Transient Response under Wide Load Range Buck-Boost Converter
(2013)
Lin, Moris
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Huang, Yung-Sheng
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Ehrhart, Andreas
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Lee, Yu-Huei
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Chiu, Chao-Chang
an authentic mode-toggled detector (AMTD) technique is proposed to achieve load and line regulations in a proposed buck-boost (BB) converter. In the case of load transient, conventional BB converter will oscillate and cannot settle to a well-regulated output voltage owing to the on-resistance of the power MOSFETs. Accurate and expeditious mode-toggled detection in the BB converter meet the requirements of load and line transient response by means of the proposed adaptively near-immediate freezer (ANIF) technique. Besides, due to pulse frequency modulation (PFM) implemented in the proposed BB converter, ultra wide load range from 10mA to 900mA can have high efficiency from 80% to 95%. Simulation results show the proposed BB converter fabricated in VIS 0.25 mu m process can be well-regulated under the input voltage ranging from 2.7V to 4.2V.
Quasiresonant Control With a Dynamic Frequency Selector and Constant Current Startup Technique for 92% Peak Efficiency and 85% Light-Load Efficiency Flyback Converter
(2014-09-01)
Kang, Yu-Chai
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Chiu, Chao-Chang
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Lin, Moris
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Yeh, Chih-Pu
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Lin, Jinq-Min
The proposed quasiresonant control scheme can be widely used in a dc-dc flyback converter because it can achieve high efficiency with minimized external components. The proposed dynamic frequency selector improves conversion efficiency especially at light loads to meet the requirement of green power since the converter automatically switches to the discontinuous conduction mode for reducing the switching frequency and the switching power loss. Furthermore, low quiescent current can be guaranteed by the constant current startup circuit to further reduce power loss after the startup procedure. The test chip fabricated in VIS 0.5 mu m 500 V UHV process occupies an active silicon area of 3.6 mm(2). The peak efficiency can achieve 92% at load of 80 W and 85% efficiency at light load of 5W.
Self-Calibrated Knee Voltage Detector With 99.65% High Accuracy for AC Charger System in 0.5 mu m 500 V UHV Process
(2014-10-01)
Chiu, Chao-Chang
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Lin, Moris
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Chang, Chih-Wei
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Meng, Che-Hao
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Yang, Hsiang-An
The self-calibrated knee voltage detector (SC-KVD) for electrical isolation primary side charger applications is proposed. The removal of the feedback network which is used in conventional designs and occupies at least 30 mm(2) can save PCB area up to around 11%. Besides, the SC-KVD can dynamically adjust the detection point to improve the accuracy to 99.65% compared to the prior arts. The test chip fabricated in 0.5 mu m 500 V UHV process can be powered on directly by the AC source owing to the 500 V ultra-high voltage device. Hence, the battery charger can be made more compact and portable than it was and the battery life can be prolonged and guaranteed.