The IZ1239M are a single chip CMOS LSI with 8-digit arithmetic operation, single memory, extraction-of-square-root, percentage calculation and auto power off function, designed for FEM LCD operation with a 1.5V power supply. The IZ1239M has special keys (C1, C2, SM, RM) for currency exchange calculations and special memory for save currency rate. The result of currency exchange operations formatted to two decimal always and rounded if it exceeds two decimal.