| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a power supply voltage monitoring circuit capable of monitoring the packaging of a sub circuit board to a main circuit board and a power supply voltage just by using only one IC for voltage monitoring. SOLUTION: This power supply voltage monitoring circuit monitors the voltage of a power supply supplied from the main circuit board through a connector provided on the sub circuit board operated by being connected through the connector to the main circuit board, and uses the IC 1-3 for voltage monitoring provided with at least one low voltage detection means and excess voltage detection means. Packaging recognition resistors R19 and R20 for turning the voltage generated by voltage dividing resistors R16-R18 to an abnormal voltage in the case that power supply connection is performed without performing the ground connection of connector connection to voltage dividing resistors R15-R18 provided between a power supply voltage circuit and the ground so as to supply a divided voltage for detection to one voltage detection circuit inside a voltage detection circuit are connected parallelly to the voltage dividing resistors R15-R18.</p> |
