Thermometer decoding structure applied to high-speed DAC circuit

Abstract

The invention provides a thermometer decoding structure applied to a high-speed DAC circuit. The structure comprises two thermometer decoders, high 4-bit data weighted by the high-speed DAC circuit unit is divided into a highest 2-bit binary code and a second highest 2-bit binary code, and the highest 2-bit binary code and the second highest 2-bit binary code are input into the two thermometer decoders respectively to obtain two groups of 3-bit thermometer codes with different weights; the two thermometer decoders are respectively connected with a DEM module, and the DEM module randomly scrambles the 3-bit thermometer codes; the two thermometer decoders are connected with a data gating module of a weight unification processing array, and 15-bit thermometer codes with consistent weights areobtained through the weight unification processing array. According to the invention, the circuit scale can be reduced, the layout area can be reduced, the high-frequency performance of the circuit can be improved, the harmonic distortion in the output signal can be suppressed, the working speed and the driving capability are high, the influence of parasitic capacitance is reduced, and the working frequency of the circuit is improved.

Description

technical field [0001] The invention belongs to the field of DAC circuit design, and in particular relates to a thermometer decoding structure applied to a high-speed DAC circuit. Background technique [0002] A digital-to-analog converter (DAC) is a circuit that converts digital signals into analog signals. In recent years, with the development of microelectronics technology and the advancement of circuit design technology, high speed current steering DAC chips with a sampling rate of GSps (Sample-per-second) have attracted more and more attention. In communication system applications, adopting high-speed, high-performance DAC chips not only greatly simplifies the system structure, but also improves the flexibility and portability of system design. It is for this reason that in many fields, high-speed, high-performance DAC chips are gradually replacing traditional analog circuits and becoming a new research hotspot in system solutions. These application areas include broa...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a thermometer decoding structure applied to the high-speed DAC circuit, which can significantly reduce the complexity of the layout, in view of the problems that the design of the high-speed DAC circuit in the above-mentioned prior art is relatively complicated, and the output signal is prone to harmonic distortion , with a simpler structure to bring better high-frequency performance, improve the dynamic performance of the circuit and SFDR

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