Numerical control electrically tunable filter

Abstract

The invention provides a numerical control electrically tunable filter. The numerical control electrically tunable filter comprises a numerical control circuit and a filter circuit, the numerical control circuit comprises a single-chip microcomputer and an operational amplifier, the filter circuit comprises a plurality of varactors and an inductor, the inductor is a chip inductor, a tube core of the single-chip microcomputer and a tube core of the operational amplifier are packaged in the same chip, and tube cores of the varactors are packaged into a whole. The tube core of the single-chip microcomputer and the tube core of the operational amplifier are packaged in the same chip, so that the space occupied by the single-chip microcomputer and the operational amplifier is reduced; the tubecores of a plurality of varactors are packaged into a whole, so that pins of other varactors are omitted; the inductor adopts a chip inductor, so that the space occupied by the inductor is reduced, the problem of long debugging period caused by inconvenient installation of a winding coil can be solved, and the production efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of electronically adjustable filters, in particular to a digitally controlled electronically adjustable filter. Background technique [0002] The bandwidth of modern RF systems is getting wider and wider, and more and more frequency bands are supported. This trend leads to higher and higher technical requirements for the electronically adjustable pre-selection filter of the RF front-end. With the needs of portable, low power consumption and multi-functional electronic products, highly integrated RF front-end circuits require filters with small size, wide frequency coverage, high receiving sensitivity, adjustable passband frequency, fast switching passband frequency and relatively low frequency. Good out-of-band suppression and other characteristics. Therefore, the design of related products and radio frequency circuits has become the current development trend. With the rapid development of the communicatio...

AI Technical Summary

Problems solved by technology

[0004] In view of this, the present invention proposes a digitally controlled electronically tuned filter to solve the problem of large volume caused by the use of discrete components and winding coils in traditional digitally controlled electronically tuned filters

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