自适应门限比较器设计  

Design of adaptive threshold comparator

作　　者：徐建[1] 王志功[1] 王欢[1] 曹翔[1] 

机构地区：[1]东南大学射频与光电集成电路研究所,江苏南京210096

出　　处：《电路与系统学报》2011年第6期6-12,共7页Journal of Circuits and Systems

摘　　要：在电子设计和应用中,CMOS电平的电子系统接口往往需要同时兼容TTL电平。这往往需要在片外接电平转换芯片,从而增加了成本和面积。同时,外接的电平转换芯片也仅仅是解决了电平转换的问题,但并没有解决由于电平门限不同而导致的脉宽失真问题,尤其在低速情况下,该问题尤为严重。本文提出了一种自适应门限比较器单元电路,不仅可以兼容TTL电平,而且可以根据输入电平自适应产生最佳的判决门限,最大程度地保证判决后‘1’、‘0’电平信号宽度相同,有效地避免了脉宽失真。电路采用CSMC 0.5μm CMOS混合信号工艺进行了流片验证。测试结果表明。该电路性能完全满足设计要求。此电路可以作为IP集成在需要TTL/CMOS接口的IC中,具有广泛的应用前景。In electrical system design, an increasing demand is to adapt both the TTL and the CMOS electrical level. Traditionally, an electrical level converter is needed off chip and it leads to an extra cost and board area. At the same time, it only deals with the electrical level conversion while the pulse width distortion still exists, because of different thresholds. In this paper, an adaptive threshold comparator is introduced as a circuit cell which is compatible with the TTL electrical level. It generates a comparative level to keep the best threshold, so the pulse width of the signals of ＇1＇ and ＇0＇ will be most likely the same and pulse width distortion is avoided. The CSMC mixed signal 0.5μm CMOS technology is used and the result of chip test is satisfied. The circuit can be used as an IP core in any needed ICs and shows a promising prospect of application.

关 键 词：自适应门限 CMOS工艺 TTL电平 比较器 脉宽失真 

分 类 号：TN47[电子电信—微电子学与固体电子学]