具新型態有限狀態機判斷機制與多相位觸發之數位式低壓降線性穩壓器

A Digital Low Dropout Regulator with New Type Finite State Machine and Multiphase Triggering

林政緯(Cheng-Wei Lin)

指導教授 ： 楊維斌

淡江大學/工學院/電機工程學系碩士班/碩士(2022年)

https://doi.org/10.6846/TKU.2022.00144

摘要

隨著穿戴式電子產品以及智聯網的蓬勃發展，IC產業也越來越專注在超低電壓、超低功耗、高整合度…等等方面設計，而數位式低壓降線性穩壓器不僅能操作在超低電壓，也因為不需使用外接電感元件故有體積小的優勢，所以較常被使用在可攜式產品中。隨著戴式電子產品的普及，延長使用時間和有效的電源管理至關重要。在未來的電源管理系統中需要輸出多組不同電壓供電，因此如何克服不同輸出間能夠不互相影響，並且抗製程、溫度、電壓變異…等，將是未來發展方向之一；隨著綠能觀念的意識抬頭，電源管理系統也更重視獵能電路的發展，因此如何設計一高效能的電源管理系統以用來結合獵能趨勢，也必然是電源管理系統最大的挑戰，以上為此論文未來研究發展的方向以及重點。
此研究採用數位同步式的設計，其電路複雜度相較於非同步式而言較為簡易，然而隨著通訊與手機產業的崛起，低壓降線性穩壓器除了不斷往快速響應的方向，系統中已逐漸以高轉換效率的理念並提高雜訊抑制能力來設計。在設計同步的時脈時頻率越高追鎖速度相對就會越快，但相對的電流效率會越來越低，因此如何在同一頻率的一個週期內做出更多的比較，就可以達到更快的鎖定速率、更高的電流轉換效率，即為本論文的研究出發點。
而為了延長可穿戴設備的電池使用時間，thermoelectric generator (TEG) harvesting是一項不可或缺的技術。為了有效利用通過 TEG 收集獲得的能量，我們設計了一種具有多相觸發功能的短建立時間數位低壓降 (DLDO) 穩壓器和一種用於 TEG 收集的新型有限狀態機。為提高跟踪速度，DLDO穩壓器採用多相觸發機制，在同一時脈週期內進行多次比較和PMOS切換。進一步，採用有限狀態機電路，有效切換模式，解決使用波峰偵測器判斷的問題。進行了模擬，並使用TSMC 90-nm 1P9M製程實現了設計，並在 0.5 V輸入和 0.45 V輸出電壓下工作。穩定時間、靜態電流和最大電流效率分別為1.05μS、10.657μA和99.73%。

關鍵字

自動頻率調變 ； 數位式低壓降線性穩壓器 ； 雙調節機制 ； 有限狀態機 ； 多相位觸發 ； 熱電 (TEG) 獵能

並列摘要

With the development of wearable electronic products and intelligent networking, the IC industry is increasingly focusing on the design of ultra-low voltage, ultra-low power consumption, high integration... etc. Digital Low-Dropout Regulator can operate in ultra-low voltage. Because not to need extra inductance, it has the advantage of small volume. It usually used in portable products. With the popularity of wearable electronic products, extended use time and effective power management are essential. In the future power management system, it is necessary to output multiple sets of different voltages for power supply. Therefore, how to overcome the ability of different outputs to not affect each other and resist process, temperature, voltage variations... etc. will be one of the future development directions; with the concept of green energy The awareness of power management has risen, and the power management system also pays more attention to the development of energy hunting circuits. Therefore, how to design a high-performance power management system to integrate the energy hunting trend is inevitably the biggest challenge for the power management system. The above is the future research of this thesis. The direction and focus of development.
This research uses a digital synchronous design, and its circuit complexity is simpler than that of asynchronous. However, with the rise of the communication and mobile phone industries, low-dropout linear regulators are constantly moving in the direction of rapid response. Has gradually been designed with the concept of high conversion efficiency and improved noise suppression capabilities. When designing a synchronized clock, the higher the frequency, the faster the lock-up speed will be, but the relative current efficiency will be lower and lower. Therefore, how to make more comparisons in one cycle of the same frequency can achieve greater Faster locking rate and higher current conversion efficiency are the starting points of this paper.
With the popularization of smart wearable devices, prolonged usage time and effective power management are crucial. To increase the battery life of wearable devices, thermoelectric generator (TEG) harvesting is an indispensable technology. For effective usage of the energy obtained through TEG harvesting, we designed a short-settling-time digital low-dropout regulator (DLDO) with multiphase triggering and a novel finite state machine for TEG harvesting. To improve the tracking speed, the multiphase triggering mechanism is used in the DLDO to perform multiple comparisons and PMOS switches within the same clock cycle. Further, a finite state machine circuit is employed to effectively switch between modes and solve the problems of using a peak detector for judgment. Simulations were preformed, and the design was implemented using the TSMC 90-nm 1P9M CMOS process and operated at 0.5 V with a 0.45 V output voltage. The settling time, quiescent current, and maximal current efficiency were 1.05μS, 10.657μA, and 99.73%, respectively.

並列關鍵字

Automatic frequency modulation ； digital low-dropout regulator ； dual adjustment ； finite state machine ； multiphase triggering ； thermoelectric generator (TEG) harvesting

參考文獻

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