The PD754304 is one of the "75XL Series" 4-bit single-chip microcontrollers with data processing capability comparable to that of 8-bit microcontrollers. The PD754303(A) has a higher reliability than the PD754304. The microcontrollers in the 75XL Series have expanded CPU functions than those of the 75X Series and can operate at a voltage of as low as 1.8 V; therefore, they are ideal for battery-driven application systems. As the one-time PROM version of the PD754304, the PD75P4308 is ideal for evaluation of a system under development or for small-scale production of application systems. Detailed information about functions can be found in the following document. Be sure to read the following document before designing.