Performance characterization of mixed-signal circuits using a ternary signal representation

Signatures used in low-cost schemes for testing analog and mixed-signal circuits do not directly represent or characterize the behavior of the device-under-test (DUT), since the lossy compression or complicated mathematical relations used can result in the loss of physical performance information. We develop a novel scheme where the signature is generated by built-in circuits based on a ternary signal representation (TSR), which represents the behavior of a signal with three levels, positive, zero, and negative. The signatures can be used directly to characterize DUTs or can be manipulated to obtain widely accepted dynamic performance parameters, such as SNR, THD, etc. Simulation results on a ΔΣ DAC and a ΔΣ ADC using TSR signatures through built-in circuits are presented to show the feasibility of the proposed method.