The invention provides a technique of a phase-change memorizer, wherein a plurality of phase-change memory units are connected in series to share a current source, and a plurality of switches control the current path of an input current provided by the current source. The technique sets a resistance value of the phase-change memory units to memorize data through controlling the switches and the input current, wherein, when different data is memorized in the phase-change memory units, the phase-change memory units are provided with different resistance sums.