Charge transfer filter with wide dimension tolerances - can be readily integrated by forming specified resonant loops

摘要

The charge transfer filter can be readily integrated and has attenuation independent of dimensional tolerance. It also requires fewer charge transfer elements by a factor of c. 10. The charge transfer elements are connected into a resonant loop (5) to give a resonant circuit (6) with two inputs (1, 4) and two outputs (2, 3). At the loop's resonant freq., the signal at the first input (1) appears exclusively at the first output (3). As the frequency deviates more and more from the tuned frequency, more and more of the input signal begins to appear at the second output (2). The reverse applies when the signal is applied to the second input (4).