A memory arrangement including a memory block and a controller. The memory block comprises a plurality of memory cells, wherein each memory cell operable to store one of a plurality of different levels of charge. The controller is configured to write (i) a first reference signal threshold into a first memory cell and (ii) a second reference signal threshold into a second memory cell. The first reference signal threshold corresponds to a first level of charge of the plurality of different levels of charge, and the second reference signal threshold corresponds to a second level of charge of the plurality of different levels of charge. Each of the first level of charge and the second level of charge is used to calibrate a read back of any of the one of the plurality of different levels of charge stored among the plurality of memory cells in the memory block.