Digital Calibration of Nonlinear Memory Errors in Sigma-Delta Modulators

作者：Lee Seung Chul^*; Chiu Yun

来源：IEEE Transactions on Circuits and Systems I-Regular Papers, 2010, 57(9): 2462-2475.

DOI：10.1109/TCSI.2010.2046243

• Analog-to-digital converter (ADC)
• correlation
• digital calibration
• low-gain amplifier
• memory error
• nonlinear distortion
• quantization noise leakage
• test signal
• Sigma Delta modulator

A digital adaptive calibration technique to linearize sigma-delta (Sigma Delta) modulators based on an output-referred distortion analysis of discrete-time integrators (DTIs) is presented. A sequential power series (a special form of Volterra series) is found sufficient to model the nonlinear memory errors in a DTI, which entails the application of adaptive polynomial transversal filtering for error correction of the modulator. Error-parameter identification is accomplished by correlating various moments of the digital output with a 1-bit pseudorandom noise, which is injected into the analog input of each DTI of the modulator. Simulations demonstrate the effectiveness of the technique in compensating the signal-dependent errors of first-and second-order Sigma Delta modulators.

• 出版日期2010-9