為解決傳統(tǒng)可視倒車?yán)走_(dá)視頻字符疊加器結(jié)構(gòu)復(fù)雜,可靠性差,成本高昂等問題,在可視倒車?yán)走_(dá)設(shè)計(jì)中采用視頻字符發(fā)生器芯片MAX7456。該芯片集成了所有用于產(chǎn)生用戶定義OSD,并將其插入視頻信號(hào)中所需的全部功能,僅需少量的外圍阻容元件即可正常工作。給出了以MAX7456為核心的可視倒車?yán)走_(dá)的軟、硬件實(shí)現(xiàn)方案及設(shè)計(jì)實(shí)例。該方案具有電路結(jié)構(gòu)簡單、價(jià)格低廉、符合人體視覺習(xí)慣的特點(diǎn)。經(jīng)實(shí)際裝車測(cè)試,按該方案設(shè)計(jì)的可視倒車?yán)走_(dá)視場(chǎng)清晰、提示字符醒目、工作可靠,可有效降低駕駛員倒車時(shí)的工作強(qiáng)度、減少倒車事故的發(fā)生。
Abstract:
A new video and text generation chip,MAX7456,was used in the design of video parking sensor in order to simplify system structure,improve reliability and reduce cost. This chip included all the necessary functions to generate user-defined OSDs and to add them into the video signals. It could be put into work with addition of just a small number of resistances and capacitors. This paper provided software and hardware implementation solutions and design example based on the chip. The system had the characteristics of simplicity in circuit structure,lower cost,and comfort for the nature of human vision. Loading road test demonstrates high video and text display quality and reliable performance,which makes the driver easy to see backward and reduces chance of accidents.