The Research And Implementation Of High Resolution And High Speed Signal Generation Method

Analog-to-Digital Converter(ADC)chips are widely used in analog signal acquisition.The chip needs to be tested before using to verify its functions and indicators.In terms of the test of high-resolution ADC chips,the resolution of the test signal needs to be 3 to 4 bits higher than the resolution of the chip according to the relevant ADC test standards.At present,the signal is generally generated by the signal generator.But the resolution of the signal generator can't meet the test requirements for the high-resolution ADC chip test.Therefore,it is necessary to study how to generate high-resolution signals.At present,the main researches at home and abroad are to use existing chips to generate higher-resolution signals.This thesis mainly studies the methods of generating high-resolution and high-speed signals used in the testing of high-resolution ADC chips.This thesis studied the signal generation method based on the time-interleaved digital-toanalog converter(TIDAC),analyzed the signal generation method and designed the specific hardware circuit.And this thesis studied the error generated in the method and proposed the corresponding digital preprocessing methods.Finally,this thesis tested the circuit and verified the indexs.The main work of this thesis include:(1)Study the demand for high-resolution and high-speed signals in integrated circuit testing and analyze the related research at home and abroad.Analyze the relevant parameters of digital-to-analog converter(DAC).Analyze and compare several current high-resolution or high-purity signal generation methods.(2)Propose a signal generation method based on time interleaving and analyze its key indicators.Propose and realize DAC circuit,isolation circuit,channel amplitude control circuit,channel switching circuit,sample-and-hold circuit,filter circuit,power supply circuit and control circuit.(3)Test and analyze the signal generation circuit.Then,according to the test results,analyze the error of the circuit and verify it by simulation.(4)Propose corresponding digital pre-processing methods to improve the quality of the output signal based on the analysis of the errors.Test the effect of digital preprocessing based on the actual circuit.(5)Aiming at the digital preprocessing of this thesis,study a method to reduce the needs for storage resources of this method and realize it on FPGA.The signal generation circuit based on the TIDAC realized the 2MSPS sampling rate when the resolution is 24-bits.The quality of the output signal is improved after the digital preprocessing.The signal-to-noise ratio(SNR)of the output sine wave can reach103.49 dB when the frequency is 10 KHz.After testing,all indicators of the circuit meet the research goals.