中圖分類號： TN919 文獻標識碼： A DOI：10.16157/j.issn.0258-7998.211483 中文引用格式： 籍明慧，裴煥斗，宮健，等. 龍芯3A4000主板VGA接口電路設(shè)計及研究[J].電子技術(shù)應(yīng)用，2021，47(11)：105-109，115. 英文引用格式： Ji Minghui，Pei Huandou，Gong Jian，et al. Design and research on VGA interface circuit of Loongson 3A4000 motherboard[J]. Application of Electronic Technique，2021，47(11)：105-109，115.
Design and research on VGA interface circuit of Loongson 3A4000 motherboard
Ji Minghui1，2，Pei Huandou1，2，Gong Jian1，2，Zhang Chuanchuan2，Zhuang Jie2
1.School of Instrument and Electronics，North University of China，Taiyuan 030051，China； 2.Shanxi 100 Trust Information Technology Co.，Ltd.，Taiyuan 030006，China
Abstract： Video Graphics Array(VGA) interface has become the most widely interface type in the display application of electronic devices with its good compatibility, mature technical advantages and low cost.Based on the functional requirements of Loongson 3A4000 motherboard,DVO bus signal is converted to analog signal by using the ADV7125, a high-performance video digital-to-analog converter(DAC),and video signal is exported through VGA interface.The VGA interface and implementation principle are introduced,the VGA video output function topology and the circuit design of VGA interface are described in detail.The results show that the interface circuit design meets the requirements of functionality and reliability for video signals of different display modes, and the video display is normal with good performance.
Key words : Loongson 3A4000；VGA interface；ADV7125；circuit design
