Voltage calculator with a sum of DC currents based on the bandgap principle and this supply voltage switch

摘要

A direct current sum bandgap voltage comparator for detecting voltage changes in a power supply. The direct current sum bandgap voltage comparator includes a summing node, current sources, and an indicator circuit. The current sources are connected to the summing node and each current source supplies a current to the summing node. The current sources also are connected to a power supply voltage, wherein the current at the summing node is equal to zero when the power supply voltage is equal to or greater than a reference voltage. The indicator circuit has an input connected to the summing node and generates a logical signal at an output that is responsive to changes in the summing node. IMAGE