Flash ADC with current inserted structure

Abstract

The invention discloses a Flash ADC with a current inserted structure, which comprises a voltage-splitting resistance network, a comparator array and a coder. An input analog signal and a reference voltage sequence output by the voltage-splitting resistance network are input to the comparator array so as to obtain a comparing output code, and the comparing output code obtains an output digital signal by the coder. The comparator array comprises a preamplifier array, an inserted flip-latch array and a flip-latch array, wherein the preamplifier arrays are arranged in parallel; each preamplifier is connected in series with a flip-latch so as to generate one comparing output value, and an inserted flip-latch is inserted between two adjacent preamplifiers so as to generate the other comparing output value; and all the comparing output values form the comparing output code of the comparator array. The Flash ADC with a current inserted structure utilizes the characteristics of devices in the prior structure and reduces the quantity of the devices by an inserted method, thereby saving the area of a chip and reducing the power consumption of the chip.

Description

technical field [0001] The invention relates to an analog-to-digital converter circuit structure, in particular to an analog-to-digital converter circuit structure utilizing the interpolation principle. Background technique [0002] Analog-to-digital converters (ADC) are widely used in instrumentation, communications, signal detection and processing, image processing, and multimedia to convert analog signals into digital signals that can be easily processed. ADCs are used in almost all electronic products related to analog signals. Different fields have different requirements for ADC, so the structure of ADC is correspondingly different. The bandwidth of some high-speed instruments such as digital oscilloscopes reaches the GHz level, requiring an analog-to-digital converter with a very high conversion speed, usually using a Flash structure, or a converter with multiple pipeline structures, combined with time interleaving technology to obtain high conversion rates; multimedi...

AI Technical Summary

Problems solved by technology

The principle of the Flash ADC is very simple, and the gap time between the digital output and the analog input is very short, and the sample and hold circuit is not required, so it is very suitable for some occasions with low resolution, but when it is necessary to make a high-resolution ADC, The number of comparators required by the Flash ADC increases with an exponent of 2, resulting in a significant increase in area and power consumption. Therefore, the number of bits in the Flash ADC generally cannot exceed 8 bits.

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