Patent ID: 10355706

Abstract:
A method and system for calibrating a time-interleaved digital to analog converter (DAC) provides equalization of frequency response misalignments in sub-DACs forming the DAC. In a calibration mode, test signals are applied to an DAC and output amplitudes and phases of are measured. From the measured values, complex values of the gains of the respective sub-DACs. hm(F) are determined and a specified target frequency response T(F) for a tandem connection equalizer-DAC is determined. For each of a plurality of test frequencies, complex values of equalizer gains Eqm are determined from Eqm(F)=T(F)/hm(F), to form equalizing frequency responses. Sets of equalizing coefficients Cm(p) pursuant to discrete Fourier transforms on Eqm(F). In an operation mode, a digital input signal is transformed input into an equalized digital signal E(n) through use of the sets of equalizing coefficients Cm(p).