| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage determination device that determines a magnitude of an input voltage in a simple configuration dispensing with a separate reference power supply.SOLUTION: A first voltage output circuit multiplies a supply voltage Vdd by a first rate to output a first voltage V1. A second voltage output circuit multiplies the supply voltage Vdd by a second rate smaller than the first rate to output a second voltage V2. A determination circuit compares a differential voltage &Dgr;V between the first voltage V1 and the second voltage V2 with a reference differential voltage &Dgr;Vs, and determines a magnitude of the supply voltage Vdd on the basis of the result of comparison. This dispenses with an existing separate reference power supply. The magnitude of the supply voltage Vdd can thus be determined in a simple configuration. The magnitude of the supply voltage Vdd can also be determined correctly even before the supply voltage Vdd reaches a rated voltage after a supply source starts operating. |
