Patent ID: 7161874

Claim:
A power generating electronic timepiece which operates using a power supply device as an energy source, said power supply device comprising at least power generating means, said power generating electronic timepiece comprising: a time measuring circuit for measuring or calculating predetermined information and outputting the resulting information; display mean for displaying time information or function information based on a signal output from said time measuring circuit; and control means for controlling states of said power generating electronic timepiece based upon the amount of power generated by said power generating means so as to switch between a first state and a second state in which less power is consumed, wherein if said power generating electronic timepiece is in said first state, said control means makes a first level determination to determine whether or not the amount of power generated by said power generating means is at most a first power generation level, and upon determining that the amount of power is at most said first power generation level, said control means switches to said second state, wherein if said power generating electronic timepiece is in said second state, said control means makes a second level determination to determine whether or not the amount of power generated by said power generating means is at least a second power generation level that is higher than said first power generation level, and upon determining that the amount of power is at least said second power generation level, said control means switches to said first state, and wherein said control means makes said first and second level determinations based on a predetermined period of detection of said amount of power or a plurality of detections of said amount of power.