Alternating current is used to sense a logic state of a memory cell that
has a resistive memory element. The memory element can be in an array and
a memory device can include the array and peripheral circuitry for
reading or sensing each memory cell in the array. The peripheral
circuitry can include a clock/control circuit providing a control signal,
which controls when a row of memory cells are sensed, a switching circuit
for receiving a cellplate count signal and a bit count signal provided by
the clock/control circuit, a cellplate line signal and a bit line signal
from the memory cell, the switching circuit producing a first output
signal and a second output signal, wherein one of the first output signal
and the second output signal is at a supply voltage and the other of the
first output signal and the second output signal alternates polarity with
each sensing operation and a comparison circuit receiving the first
output signal and the second output signal and outputting a signal
corresponding to the logic sate of the memory cell.