Voltage division integral type time constant calibration circuit of on-chip active RC filter

Abstract

The invention discloses a voltage division integral type time constant calibration circuit of an on-chip active RC filter. The voltage division integral type time constant calibration circuit comprises a comparator circuit, a digital controller, an integrator circuit, a proportional resistance circuit and a switching circuit. The proportional resistance circuit is connected with the double-end input end of the integrator circuit, and the output end of the integrator circuit is connected with the input end of the switch circuit. The output end of the switch circuit is connected with the comparator circuit, and the comparator circuit is connected with the digital controller. The digital controller is connected with the digital control word end of the digital programmable capacitor of the integrator circuit. By adopting the integrator circuit, the proportional resistance circuit and the switching circuit, the requirement on an accurate current source is saved, the complexity of circuit design is reduced, the power consumption of a chip is reduced, the calibration precision is improved, and on-chip integration is easy.

Description

technical field [0001] The invention belongs to the field of electronic technology, and further relates to a voltage-dividing integral type time constant calibration circuit of an active resistance capacitance RC (resistance capacitance) filter in the field of microelectronic technology. The invention can be applied to an active RC filter in the front end of a radio frequency receiver in the field of wireless communication, and a calibration circuit for performing frequency calibration. Background technique [0002] With the development of radio frequency integrated circuits, the demand for high-performance active RC filter calibration circuits is increasingly urgent, and the improvement of the performance of on-chip calibration circuits has become a research hotspot in the field of microelectronics technology today. The active RC filter is a filter composed of RC components and operational amplifiers called an RC active filter. Its function is to pass signals within a certa...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to address the above-mentioned deficiencies in the prior art, and propose a voltage-dividing-integral time constant calibration circuit of an active RC filter on chip to solve the on-chip filter application system due to the need to provide additional precision current mirrors on-chip. The difficulty of integrated integration and the problem of calibration deviation caused by the mismatch of the current mirror improve the integration of the calibration circuit

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