Analysis of Combined Channel Mismatch Effects in Time-Interleaved ADC Systems

A time-interleaved ADC system is an alternative choice to implement a high speed rate ADC with relatively low speed ADCs operating at interleaved sampling times. However, the system resolution always degrades due to mismatches such as offset, gain, bandwidth and timing mismatches between different ADC channels. Previous analyses showed these mismatch effects individually. This paper derives explicit formulas for the mismatch effects when the gain, offset, timing and bandwidth mismatches exist together. Several graphs calculated from these formulas, which would be useful for designing a two-channel interleaved system, are provided too. The formulas can also be used for calibration algorithms to compensate for the channel mismatch effects.