Patent ID: 7187961

Claim:
A semiconductor device, comprising: a sensor for detecting a physical quantity of an object to be measured; an A/D conversion circuit for amplifying a signal detected by said sensor and for converting the amplified signal to a digital signal; a microprocessor for processing said digital signal; a memory for storing information based on said digital signal; a transmission circuit for transmitting said digital signal processed by said microprocessor to the outside; and a power generator for generating electric power to be supplied to said sensor, said A/D conversion circuit, said microprocessor, said memory, and said transmission circuit, respectively, wherein said semiconductor device further includes a power supply control circuit and a capacitor; wherein said power supply control circuit is configured so as to control whether to supply electric power generated by said power generator to said sensor, said A/D converter, said microprocessor, said memory, and said transmission circuit; and wherein said capacitor is configured so as to accumulate said electric power generated by said power generation unit.