Time-Interleaved ADC Timing Calibration for Clock Skew Errors

The patent applies preliminary action by measuring time skew errors between clock signals before they affect the conversion process, and pre-calculating compensation values using correlation measurements. The system performs calibration operations in advance to determine skew parameters, then uses these pre-computed values to correct the clock timing relationships during normal operation, preventing data distortion before it occurs.

The patent implements feedback by continuously measuring the correlation between data samples from adjacent ADCs, detecting time skew errors in real-time, and using these measurements to adjust clock signal phases. The system creates a closed-loop control where conversion performance metrics feed back to the clock generator, enabling dynamic compensation that maintains high conversion accuracy despite timing variations.

The patent applies universality by designing the timing calibration circuit to perform multiple functions: it measures time skew errors, calculates compensation values, generates corrected clock signals, and validates conversion accuracy. The same correlation calculation unit is used for both calibration and normal conversion operations, and the clock generator serves both as a source of original clock signals and as a device for applying phase corrections based on measured skew.

The patent uses an intermediary approach by introducing a correlation calculation unit that acts as a mediator between the raw data samples and the time skew measurement. Instead of directly measuring clock signal timing differences, the system measures correlations in the data domain, which indirectly reveals the time skew. This intermediary measurement method simplifies the calibration circuit by avoiding direct clock signal manipulation and using readily available data samples from the conversion process.