Browsing by Author "Chung, Ming-Jie"

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A Single-Inductor Triple-Input-Triple-Output (SITITO) Energy Harvesting Interface with Cycle-by-Cycle Source Tracking and Adaptive Peak-Inductor-Current Control
(2017-01-01)
Liu, Chi-Wei
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Chung, Ming-Jie
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Lee, Hui-Hsuan
;
Liao, Pei-Chun
;
Chen, Po-Hung
In this paper, a single-inductor triple-input-triple-output (SITITO) buck-boost converter with cycle-by-cycle source tracking (CCST) is developed for multi-source energy harvesting. The proposed CCST is capable of harvesting power from the PV and TEG simultaneously, and automatically selects the appropriate source according to the maximum power point (MPP) of the transducers in each switching cycle. The converter provides two regulated outputs for the analog (V-OUT1 = 1.2 V) and the digital (V-OUT2 = 0.4-0.6 V) circuits, while storing the excess energy in a storage capacitor (C-OUT3). An adaptive on-time (AOT) circuit with an adaptive peak-inductor-current (APIC) control is developed for dynamically adjusting the on-time based on the input voltage (V-IN) to obtain high conversion efficiency under different V-IN. The proposed converter achieves a peak efficiency of 84.4% with an available input voltage of 0.05 V to 0.8 V. Compared to the conventional constant peak-inductor-current (CPIC) control, the proposed APIC improves 11 % efficiency at low V-IN.
An 82.9%-Efficiency Triple-Output Battery Management Unit for Implantable Neuron Stimulator in 180-nm Standard CMOS
(2019-05-01)
Liu, Chi-Wei
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Chen, Yi-Lun
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Liao, Pei-Chun
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Lin, Shiau-Pin
;
Wang, Ting-Wei
This brief presents a high-efficiency battery management unit combining a single-inductor dual-output (SIDO) buck converter with two charge pumps (CPs) to provide three voltage levels (6 V, -6 V, and 2 V) for neuron stimulators in implantable medical devices. The stacked power stage in the buck converter mitigates the voltage stress issue in the power stage to manage 3.2-4.8 V battery voltage. By cascading a buck converter and CPs, the voltage across the CP power stage is reduced to generate 6 V and -6 V high voltage outputs without using high voltage devices. As a result, the proposed battery management could provide 6 V, -6 V, and 2 V output voltages from 3.2 to 4.8 V input voltage using a 180-nm standard CMOS process. The measurement results demonstrate that the proposed battery management achieved a peak efficiency of 82.9% with an available input voltage of 3.2-4.8 V.
Dual-Source Energy-Harvesting Interface With Cycle-by-Cycle Source Tracking and Adaptive Peak-Inductor-Current Control
(2018-10-01)
Liu, Chi-Wei
;
Lee, Hui-Hsuan
;
Liao, Pei-Chun
;
Chen, Yi-Lun
;
Chung, Ming-Jie
In this paper, we present a single-inductor triple-input-triple-output (SITITO) buck-boost converter in a 0.18-mu m CMOS process for dual-source energy harvesting. The converter operates in the single-source mode, dual-source mode (DSM), and backup mode automatically by detecting the input and output conditions. Converter operation in the proposed DSM enables extraction of power from both a photovoltaic cell and a thermoelectric generator in one switching cycle for efficient power extraction. The cycle-by-cycle source-tracking approach selects the appropriate input source according to the maximum power point of the energy transducers. The adaptive on-time circuit with the proposed adaptive peak-inductor-current (APIC) control adjusts the on-time of power transistors to obtain high conversion efficiency under different input voltages. The experimental results demonstrate that the proposed SITITO converter has a peak efficiency of 84.4%. When compared with the conventional constant peak-inductor-current control, an efficiency improvement of 11% is obtained via the proposed APIC control.
Energy Harvesting Techniques: Energy Sources, Power Management and Conversion
(2015)
Fan, Philex Ming-Yan
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Wong, Oi-Ying
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Chung, Ming-Jie
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Su, Tze-Yun
;
Zhang, Xin
Energy harvesting techniques have been developed more than a decade and received much attention in realizing long-term energy autonomous microsystems. Many converter topologies and circuit techniques have been reported to effectively convert the harvested energy to usable outputs. In this paper, major green energy sources as well as the equivalent circuits are reviewed. In addition, maximum power point tracking (MPPT) technique and power conversion topologies are also included.