Error correcting encoder for D/A converter

Abstract

The invention is an encoder to convert thermometric code, containing a first-stage circuit, a second-stage circuit and a third-stage circuit. The first-stage circuit converts a '00100' bit stream in the thermometric code to '00000' and '11011' bit stream to '11111', respectively. The second-stage circuit is connected to the first-stage circuit and converts a thermometric code outputted by the first-stage circuit to an N-select-1 code according to the position of '000111', '001011' or '011001' bit stream in the thermometric code. The third-stage circuit is connected to the second-stage circuit and converts the N-select-1 code to a 2-modulus code.

Description

technical field The present invention relates to an encoder, and more particularly to an error correcting encoder for an analog to digital converter. Background technique Please refer to FIG. 1, which is a comparison table of thermometer code (thermometer), N code (one-of-N), gray code (gray), binary code (binary) and decimal code (decimal). Figure 1 shows the representation methods of various encodings of decimal numbers 0-15, where the binary code is represented by 4 bits, the thermometer code is represented by 24-1 bits, and the decimal number represents the number of times 1 appears in the temperature code , the N 1 code is represented by 24 bits, and only one 1 will appear in each N 1 code, and the size of the N 1 code is determined by the bit weight (weight) where the 1 is located, and the Gray code also uses 4 bits The biggest difference between it and the binary code is that the two adjacent numbers of the Gray code have only one bit difference. In the structure o...

AI Technical Summary

Problems solved by technology

From the above, it can be known that bubble errors will cause large errors in signal conversion. However, it is difficult for the known analog-to-digital converter 10 to avoid bubble errors when converting analog signals into thermometer codes. When bubble errors occur , if the N 1 code converted by the thermometer code is directly converted into a binary code, a

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