Successive approximation type analog-to-digital converter and error code detection based digital correction method thereof

Abstract

The invention discloses a successive approximation type analog-to-digital converter and an error code detection based digital correction method thereof. The correction method comprises steps as follows: 1) an initial value of a correction capacitor is set; 2) a digital correction logic circuit randomly acquires digital output codes of a converter; 3) the output codes are divided into two groups, namely, a group A and a group B, and the output codes are counted by 8-bit counters A and B; 4) if the overflow speed of the 8-bit counter B is higher than that of the 8-bit counter A, the correction capacitor is increased by 0.5 C; if the overflow speed of the 8-bit counter A is higher than that of the 8-bit counter B, the correction capacitor is decreased by 0.5 C; if the overflow speed of the 8-bit counter B is equal to that of the 8-bit counter A, the value of the correction capacitor is unchanged; 5) after Step 4) is finished, the digital correction logic circuit clears the 8-bit counters A and B, and Steps 2)-4) are repeated. According to the correction method, the specific correction process and the conversion process of the successive approximation type analog-to-digital converter are conducted synchronously, no additional correction period or correction time is required, real-time response can be made to PVT change, and the method has the advantage of capability of realizing real-time correction.

Description

technical field [0001] The invention belongs to the field of digital-analog hybrid integrated circuit design, and relates to a successive approximation analog-to-digital converter and a digital correction method based on error code detection. Background technique [0002] The analog-to-digital converter can convert analog signals in nature into digital signals suitable for computer processing. It is a key module in the information technology industry and an important direction in the field of integrated circuit design. With the development of modern wireless communication technology, analog-to-digital converters are developing towards high precision, high speed and low power consumption. Compared to pipelined ADCs and oversampling ADCs, successive approximation ADCs have relatively low power consumption, moderate to high speed and accuracy, while being able to fully benefit from the size of modern integrated circuits increasingly shrinking. The comprehensive advantages of ...

AI Technical Summary

Problems solved by technology

Process mismatch and parasitic capacitance can cause integral nonlinearity and differential nonlinearity errors of SACs, which can greatly degrade the actual accuracy of SARs

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