Cascade oversampling analog-to-digital modulator

Abstract

The invention discloses a cascade oversampling analog-to-digital modulator. The cascade oversampling analog-to-digital modulator comprises two two-order one-bit modulation feedback loops and a noise offset circuit. Each two-order one-bit modulation feedback loop comprises two integrators, a one-bit analog-to-digital converter and a one-bit digital-to-analog converter. The noise offset circuit comprises a plurality of triggers D and a plurality of digital integrators composed of the triggers D. The analog output end of the two-order one-bit modulation feedback loop A is connected with the input end of the two-order one-bit modulation feedback loop B, the digital output end of the two-order one-bit modulation feedback loop A is connected with the input ends of the triggers D of the noise offset circuit, the digital output end of the two-order one-bit modulation feedback loop B is connected with the input ends of the digital integrators of the noise offset circuit, and the output of the noise offset circuit is the output of the whole cascade oversampling analog-to-digital modulator. According to the cascade oversampling analog-to-digital modulator, the circuit structure can be simplified and high precision can be achieved while the stability of the system is guaranteed.

Description

technical field [0001] The invention relates to a cascaded oversampling analog-digital modulator, which belongs to the technical field of microelectronics. Background technique [0002] The integral triangle analog-to-digital converter (A / D) is an oversampling analog-to-digital converter, which uses oversampling, noise shaping and digital filtering technologies to reduce the requirements for matching precision of components and components, and can realize traditional Nano The precision that cannot be achieved by the Quest rate analog-to-digital converter is currently the mainstream technology for realizing high-precision analog-to-digital modulators, and has broad application prospects in the fields of sensors, digital audio, ADSL, and wireless communications. [0003] Sigma-Delta Modulator (SDM, Sigma-Delta Modulator) can be divided into one-order or multi-order, one or more bits, etc. Among them, although the 1-bit sigma-delta modulator has good linearity, it cannot meet ...

AI Technical Summary

Problems solved by technology

However, if the order is increased, the state will be unstable, and if the number of bits is increased, a nonlinear feedback signal will be introduced without additional processing, making the summed signal nonlinear and the linearity of the overall system reduced. In some cases, additional algorithms or circuits are required to maintain or correct the linearity, resulting in an additional burden on the system

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