CTD LINE HAVING A PLURALITY OF CTD ELEMENTS

摘要

In prior art filters using CTD (charge transfer device) lines and having relatively narrow band widths, the capacitance ratios of the CTD lines employed differ significantly, which leads to difficulties with respect to tolerances in the manufacturing process. The present invention provides a CTD line consisting of a plurality of CTD elements with which one obtains any random division ratio without the influence of the tolerances having a negative influence at the same time. The CTD line has a plurality of CTD elements with separating ridges for charge division oriented in the direction of charge transport, the ridges being applied as thick oxide ridges or channel-stop regions. The separation ridges for successive stages are disposed to yield a charge division in the ratio of approximately 1:1. A plurality of summation sections are provided between the division stages, all remaining partial charges with the exception of only one partial charge being summed in the summation sections.