A method for ZQ calibration for a data transmission driving circuit of each memory die in a memory chip package in which memory dies are stacked, includes generating a reference current through a reference resistor connected between a power terminal supplying a power voltage of the data transmission driving circuit and a ground terminal and a first transistor that is diode-connected; supplying first currents corresponding to the reference currents to a pull-up driver of each memory die; performing ZQ calibration of a pull-up driver of a corresponding memory die by comparing a first voltage formed by each first current with a reference voltage formed by the reference current in each of the plurality of memory dies; and performing ZQ calibration of a pull-down driver of the corresponding memory die based on an output impedance of the ZQ calibrated pull-up driver in each of the memory dies.