Abstract
With the development of filter system in the various types of electronic devices, normal filter will generate error when it works, and it will affect the overall system accuracy. Low precision filters will cause many adverse consequences, the subject of integrated programmable filters based on single chip programmable filter design has an extremely important significance. When the input signal amplitude changes, with the front stage programmable gain amplifier module, we can achieve precise control to keep the output signal amplitude remain stable;
while the input signal changes frequently, we accomplish the RC network switch with monolithic integrated programmable filter chip and simple peripheral device by sampling program data;
By microcontroller programming, we accomplish low-pass, high pass filtering on a variety of low-frequency signals, and filter parameters such as center frequency, quality factor can be set properly according to different applications.
Thus, we improve the performance and targets of filter, at the same time, we avoid the challenge which includes: the inaccuracy of characteristic parameter in traditional active filter, the complex design and debug of circuit, and it can be well applied in suitation which signal frequency and amplitude changes in a wide range of place,it is easy to operate and has excellent performance.The study aims to design a Programmable filter which its amplifier gain,low-pass or high pass filter passband and the cut-off frequency can be set.
Keywords: Programmable filter SCM