| 摘要 |
PURPOSE:To provide a power failure backup circuit capable of exactly and easily measuring the backup current of the power failure backup circuit, which holds the operating state of a static RAM or the like when power supply is lost, in an automatic system. CONSTITUTION:In the power failure backup circuit is composed of a diode 2 forward connected to a power source 1, low resistor 3 connected to the negative side of this diode 2, capacitor or secondary battery 5 connected to this low resistor 3 and high resistor 4 connected between the connecting point of the power source 1 and the diode 2 and the connecting point of the low resistor 3 and the capacitor or secondary battery 5, the connecting point of the power source 1 and the diode 2 is used as an output terminal to a circuit 6 to be backed up, and terminals 41 and 42 for backup current measurement are provided at both end parts of the high resistor 4. |
