现代电子技术
現代電子技術
현대전자기술
MODERN ELECTRONICS TECHNIQUE
2013年
15期
160-162
,共3页
高速 CCD%预放电路%寄生电容%高频补偿
高速 CCD%預放電路%寄生電容%高頻補償
고속 CCD%예방전로%기생전용%고빈보상
high-speed CCD%preamplification circuit%parasitic capacitance%high-frequency compensation
高速成像应用中，CCD 的输出通道数较多，且每个通道的速度也很高。多通道输出需要多个放大器对信号进行放大。当放大器数量较多时，电路板布局时很难使放大器靠近 CCD 放置。较长的电路板走线产生的寄生电容和 CCD 输出电阻形成的低通电路严重限制了带宽。因此，在电路设计时采用了高频补偿方法解决了带宽限制的问题。在电路板设计时采用去除运算放大器反馈端地平面的方法避免了放大电路自激振荡。
高速成像應用中，CCD 的輸齣通道數較多，且每箇通道的速度也很高。多通道輸齣需要多箇放大器對信號進行放大。噹放大器數量較多時，電路闆佈跼時很難使放大器靠近 CCD 放置。較長的電路闆走線產生的寄生電容和 CCD 輸齣電阻形成的低通電路嚴重限製瞭帶寬。因此，在電路設計時採用瞭高頻補償方法解決瞭帶寬限製的問題。在電路闆設計時採用去除運算放大器反饋耑地平麵的方法避免瞭放大電路自激振盪。
고속성상응용중，CCD 적수출통도수교다，차매개통도적속도야흔고。다통도수출수요다개방대기대신호진행방대。당방대기수량교다시，전로판포국시흔난사방대기고근 CCD 방치。교장적전로판주선산생적기생전용화 CCD 수출전조형성적저통전로엄중한제료대관。인차，재전로설계시채용료고빈보상방법해결료대관한제적문제。재전로판설계시채용거제운산방대기반궤단지평면적방법피면료방대전로자격진탕。
There are much more CCD output channels in high?speed imaging application and the speed of each channel is also much higher. Multiple amplifiers are needed to amplify the multiple output signals. It is very hard to make the amplifiers close to the CCD when the printed circuit board layout is carried out in the case of application of more amplifiers. Thus,the bandwidth is significantly limited by the parasitic capacitance produced by long wires of printed circuit board,and the low pass circuit formed by the output resistance of CCD. In order to eliminate the bandwidth limitation,the high frequency compensation is used in the circuit design. A method to cut out the ground plane at the feedback terminal of the operational amplifier is adopted to avoid self?oscillation of the amplifier circuit.
