Dynamic reference voltage calibration integrated FeRAMS

摘要

A FeRAM includes a reference voltage calibration circuit that evaluates FeRAM cells and selects reference voltages for reading the FeRAM cells. Calibration of the reference voltage can be performed dynamically during normal operation of the FeRAM so that the reference voltage tracks changes in FeRAM cell performance that may be associated with temperature or aging effects. Dynamic calibration during normal use eliminates the need for a reference voltage calibration process during manufacture of the memory. The calibration circuit can further be connected to redundancy circuitry that replaces FeRAM cells that the calibration circuit determines are weak.