The M37225M6-XXXSP, M37225M8-XXXSP, and M37225ECSP are single-chip microcomputers designed with CMOS silicon gate technology. They have a OSD, I2C-BUS interface, PWM output, and 12 V withstand, so it is useful for a channel selection system for TV. The features of the M37225ECSP are similar to those of the M37225M6-XXXSP except that the chip has a built-in PROM which can be written electrically. The difference between M37225M6-XXXSP and M37225M8-XXXSP are the ROM size. Accordingly, the following descriptions will be for the M37225M6-XXXSP.