Power efficiency improvement method using coupled inductor in DC-DC power supply for AMOLED panel
- 주제(키워드) power efficiency , AMOLED
- 발행기관 고려대학교 대학원
- 지도교수 김수원
- 지도교수 박철우
- 발행년도 2017
- 학위수여년월 2017. 2
- 학위구분 석사
- 학과 대학원 전기전자공학과
- 세부전공 직접회로
- 원문페이지 63 p
- 실제URI http://www.dcollection.net/handler/korea/000000072870
- 본문언어 영어
- 제출원본 000045897542
초록/요약
To increase battery life time is the most important concern in the smart phone and tablet industry. The portion of battery power consumed in the display panel of mobile device is very large [1]. The display size, resolution and brightness have been increasing every year in order to meet the consumer’s needs. Therefore, the researches on reducing power consumption in the display panel are continuing as well [2]. The display in a mobile device is classified into two types which are the Active Matrix Organic Light Emitting Diode (AMOLED) and the Liquid Crystal Display (LCD). Because the organic compound material comprising RGB pixels emit light for itself in the AMODED display, the backlight is not needed. This is the reason why AMOLED’s thickness is smaller than the LCD’s in general. Another virtue of AMOLED compared to LCD is that it can make true black color by turning off all RGB pixels. This leads to very high contrast ratio [3]. For the bias voltages of AMOLED Display, a Boost converter and a Buckboost converters are used. The Boost converter makes higher output voltage than the input voltage from the lithium-ion battery cell. The Buckboost converter makes the negative output voltage from the positive input voltage. The DC to DC converter (DC-DC) such as the Boost converter and the Buckboost converter uses the power inductor in order to transfer the energy from a DC-DC to the load filtering switching noise. The iron loss of power inductor is the one of several factors which reduces the power efficiency on a power supply system [4]. The study on reducing iron loss in power inductor is ongoing [5][6][7]. Recently, many papers about multi-phase DC-DC convertor with coupled inductor used to increase performance are issued [8][9]. However, there were no attempt to couple the inductors between the heterodyne DC-DC like Boost converter and Buckboost converter. This thesis presents that the coupled inductor can be useful in the power supply system for the AMOLED Panel.
more목차
Abstract i
Table of Contents iii
List of Figures v
List of Tables vii
1. Introduction 1
1.1 Motivation 1
2. Background 3
2.1 AMOLED Display for mobile device………………………………..3
2.2 The principles on DC to DC converter (DC-DC). 4
2.2.1. Boost converter operation analysis 4
2.2.2. Buckboost converter operation analysis 9
2.3 Magnetics fundamentals……………………………………………13
2.3.1 Transoformer modeling…………………………………………14
2.3.2 Core loss in magnetics………………………………………..…15
3. Power Supply system for AMOLED panel 22
3.1 The previous power supply system for AMOLED panel 22
3.2 The proposed power supply system for AMOLED panel 25
3.2.1 The inductance trade-off according to the converter state…..26
3.2.2 The operational princial of coupled inductor………………….28
4. Simulation and experimental result 36
4.1 Circuit simulation 36
4.2 Experiment result 43
4.3 Performance comparison 46
5. Conclusion 48
Bibliography 50
