在目前的科技世代裡，手機、平板等手持式裝置是普遍必須的產品，而這些產品多數以電池作為一個能源的供應。一般情況下，這類產品的內部電路所需要之電壓必須利用降壓型轉換器來將相對較高的電池電壓進行降壓轉換。本論文提出「改善負載暫態響應之雙模式控制降壓型轉換器」，同時使用漣波固定導通時間控制法與電壓磁滯控制法所形成的雙模式控制，以結合電壓磁滯控制模式之優點，來達到改善負載暫態響應的功能，並且提出因責任週期全開所導致之電壓過衝/下衝的改善方法，其使用電流感測電路，對電感電流與負載電流進行偵測，來計算出因輸出負載變動導致輸出電壓降低之時間，並根據此時間來調整暫態時之責任週期，來使輸出電壓快速回至穩態之電壓。本論文採用 TSMC 0.18 μm 1P6M CMOS 製程實現，晶片內部包含輸入/輸出焊墊(I/O PADs)面積為1.545 × 1.417 mm2。本論文操作切換頻率為1MHz，輸入電壓為3.3 V，輸出電壓為1.8 V，電感、輸出電容分別為 10 μH、4.7 μF，輸出負載範圍為100 mA至900 mA。

關鍵詞：漣波固定導通時間控制、電壓磁滯控制、雙模式控制、加快暫態響應、降壓型轉換器

In today's technological era, handheld devices like smartphones, tablets, and others have become ubiquitous necessities. Most of these devices rely on batteries as their primary power source. Typically, the internal circuits of such devices require a voltage reduction using buck converters to lower the relatively high battery voltage. This paper proposes a “Dual Mode Control Buck Converter for Improved Load Transient Response.” It employs a dual-mode control formed by Ripple Base Constant On Time Control and Voltage Hysteretic Control. This combination leverages the advantages of voltage hysteretic control to achieve improved transient response. Additionally, it presents a method to mitigate voltage overshoot/undershoot resulting from duty cycle full-on situations. This method utilizes a current sensing circuit to detect inductor current and load current, calculating the time of output voltage drop due to changes in the output load. Based on this time, it adjusts the duty cycle during transients to rapidly restore the output voltage to its steady state. This paper's implementation uses the TSMC 0.18 μm 1P6M CMOS process, with the chip's area comprising Input/Output Pads measuring 1.545 × 1.417 mm². The operational switching frequency is 1MHz, with an input voltage of 3.3 V and an output voltage of 1.8 V. The inductor and output capacitors are 10 μH and 4.7 μF, respectively, and the output load range spans from 100 mA to 900 mA.

Keywords: Ripple Based Constant On Time Control, Voltage Hysteretic Control, Dual Mode Control, Improved Transient Response, Buck Converter

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