Microprocessor equipped with an A/D converter

摘要

A microprocessor which can be used as a microprocessor with 8-bit A/D converter or 10-bit A/D converter is disclosed. Voltage comparator 2 compares the analog input signal AIN level with the reference voltage VREF, and then generates the comparative signal CP. The comparative signal CP is supplied to the serial conversion register 3 in order and is stored as the converted data DC. The upper 8 bits of the converted data DC stored in the serial conversion register 3 are supplied to the conversion result register 4A, and the lower 2 bits are supplied to the conversion result register 5A. In this way, in the case where this microprocessor is used as an microprocessor with a built-in 8-bit A/D converter, the microprocessor only ignores the contents of the conversion result register 5A.