DATA STORAGE DEVICE AND SEARCHING METHOD FOR READING VOLTAGE THEREOF

A method of searching for read voltages includes: respectively reading a memory segment through read voltages to obtain a sampling data, wherein the read voltages are composed of pairs of adjacent read voltages, and the memory segment is from a non-volatile flash memory; counting the number of first bits in each sampling data, wherein the numbers of first bits correspond to the read voltages respectively; obtaining number differences of the first bits corresponding to the pairs of adjacent read voltages; calculating a coefficient matrix according to the read voltages and the differences of the number of first bits; calculating fitting values according to the read voltages and the coefficient matrix, wherein the fitting value corresponds to the read voltage respectively; and selecting a read voltage corresponding to a minimum value among the fitting values to read the memory segment to perform an error correction program.