本技術報告主要介紹的是當前業界應用於液晶電視的電源供應器架構,以及針對量產品設計的構思與應用。其內容包含:1.升壓型轉換器(Boost Converter),也就是主動式功率因數修正器之動作原理,在交流轉為直流架構下,提供半橋諧振電路作為一個穩定的電源輸入。2.直流脈波調變轉換器(pulse-width modulation,PWM)部分,其電路架構是採用半橋諧振式,在切換過程中,以求達到零電壓切換,減少功率元件開關損失,使其整個電路工作在效率較高的狀態。 升壓型轉換器部分係採用ON Semiconductor公司出產的NCP1607 IC,用以製作主動式功率因子修正及升壓電路。其搭配脈波寬度調變轉換器係採用Sanken公司出產的SSC9512S IC,用以作為主電源架構直流轉換。主電路架構電路係採用半橋諧振式電路,其目的在於調變工作週期,使轉換器上臂開關工作在零電流切換(Zero Current Switch, ZCS),下臂開關工作在零電壓切換(Zero Voltage Switch, ZVS),以降低開關元件在導通或截止時的交越損失。 最後將兩切換電路整合在同一PCB;利用電視系統提供之空間,輸入、輸出方向排列,考慮安全規範,不干擾信號源,及對流散熱方面規劃設計,呈現所要求的量產品。
In this technical report, integration of two subsystems, a booster ac-dc converter and half bridge dc-dc converter with pulse-width modulation, is presented, and its results are suitable for high-voltage and high-power electronic applications. This booster ac-dc converter can provide power factor correction for not only reducing harmonic distortions of the input current, but also enhancing the rated power and system efficiency. The half bridge dc-dc converter armed can reach soft zero-current-zero-voltage switching and curtail a switch power loss during the conversion. The integration of two subsystems is implemented in a PCB. The booster ac-dc converter uses the device “NCP1607 IC” made by the ON Semiconductor, which is operated on the boundary-conduction- mode in our design. The main power dc-dc converter utilizes the device “SSC9512S IC” manufactured by the Sanken, which executes pulse-width modulation so that it can operate the upper part on zero-current mode, while the lower part on zero-voltage mode for a power loss. The results of this integration of two subsystems show that our design has no signal interference and can also have a good function of heat dissipation.