| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power source voltage setting circuit which automatically sets an optimum voltage for each device by automatically detecting a variation in the computer device. <P>SOLUTION: When a voltage setting mode is set by a mode switch 8 and a CPU 10 is started, the CPU 10 sets a flag for a Hi flag register 2, raises a voltage to conduct a High voltage margin test while recording a setting voltage value in a High measurement register 3, sets a flag for a Lo flag register 2, lowers the voltage to conduct a Low voltage margin test while recording the setting voltage value in the Low measurement register 3, and calculates a reference voltage of the device on the basis of the setting values of the High measurement register 3 and the Low measurement register 4, sets an optimum voltage value for a voltage setting register 6. If a normal operation mode is set by the mode switch 8 and the CPU 10 is started, a power source 7 refers to the setting value of the voltage setting register 6 and outputs the voltage. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
