| 摘要 |
PURPOSE:To reduce the power consumption by monitoring ambient temperature, and raising the power source voltage when the ambient temperature is high and lowering the power source voltage to a designed power source voltage when low. CONSTITUTION:This device consists of a control circuit 5, a power source 3-1 which generates a low output voltage, a power source 3-2 which generates a high output voltage, a temperature sensor 2, a voltage control circuit 1, and a power source voltage changeover switch 4. The power source voltage changeover switch 4 is connected normally to the power source 3-1 (4.5V) which generates the low output voltage. The voltage control circuit 1 measures the temperature information 101 from the temperature sensor 2 and judges that the operation environment gets worse when prescribed temperature is exceeded, thereby switching the power source voltage changeover switch 4 to the power source 3-2 (5V) which generates the high output voltage. Consequently, the source voltage of the control circuit 5 becomes high, so the control circuit 5 can perform high speed operation and also operates normally even in the inferior environment. Namely, the power source voltage is adaptively controlled so that the operation margin that the circuit has approaches zero as much as possible. |
