Mismatch sensitivity of a simultaneously latched CMOS sense amplifier

Derives a new formula for the sensitivity of a vertically matched CMOS sense amplifier, of the type used in dynamic-RAMs (DRAMs), to threshold voltage mismatch, parasitic capacitance mismatch, transconductance mismatch, and bit-line load capacitance mismatch. The formula yields insight into the DRAM sensing operation. The authors derive a sensitivity formula for this sensing scheme, using perturbation theory. The perturbation approach is rigorous: it avoids most approximations and ad-hoc assumptions, it introduces no free constants to be determined from simulations, and it yields an explicit closed-form solution. The formula agrees well with simulations. It is inherently slightly conservative and thus appropriate for use in design.<
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