Capacitor array digital-to-analog converter circuit for high-speed successive approximation analog-to-digital converter

Abstract

The invention relates to a capacitor array type digital to analog converter circuit of a high-speed successive approximation type analog to digital converter. The capacitor array type digital to analog converter circuit comprises a switching capacitor array of a full differential non-binary weight, the input end of the switching capacitor array is respectively connected to an input signal VIP, an input signal VIN, a reference high level VREFT and a reference low level VREFB, the output end of the switching capacitor array is connected with the input end of a dynamic comparator through a sampling switch, the output end of the dynamic comparator outputs a comparison result signal Yi to the input end of a switch control logic generating circuit, and the output end of the switch control logic generating circuit outputs a plurality of switch control signals to the switching capacitor array of the full differential non-binary weight. The capacitor array unit of the capacitor array type digital to analog converter circuit provided by the invention adopts a C-2C capacitor structure, and the total input capacitance under a sampling mode is a fixed constant value, so that the design of an input voltage buffer is simplified, and meanwhile the bandwidth of the input signals is expanded; the driving capacity of a differential reference circuit is greatly reduced, and thus the power consumption of the reference circuit is reduce to achieve the low power consumption demand of the entire circuit system.

Description

technical field [0001] The invention relates to the technical field of analog integrated circuit design, in particular to a capacitance array digital-analog converter circuit of a high-speed successive approximation analog-to-digital converter. Background technique [0002] With the development of advanced manufacturing process technology for integrated circuits, the semiconductor process has been developed to nodes below 20 nanometers. Advances in semiconductor technology have brought features such as low power supply voltage, low power consumption, high integration and small chip area to digital circuits. However, for analog circuits, the design of traditional devices has become more complex and difficult to implement. Therefore, it has become a research hotspot to convert as many functions as possible from the analog domain to the increasingly powerful digital domain in the circuit system. [0003] The analog-to-digital converter is the bridge and link between the digita...

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