Apparatus for reducing noise from multiple switching regulators

摘要

An apparatus for reducing switching regulator noise from outputs of multiple switching regulators is disclosed. The apparatus includes an operational amplifier, an capacitor, a resistor and a pair of diodes. The switching regulators are connected in series to provide a positive output rail and a negative output rail. The output of the operational amplifier in connected to an inverting input of the operational amplifier and a positive sensing input of one of the switching regulators. The non-inverting input of the operation amplifier is connected to the positive output rail of one of the switching regulator via the capacitor. The resistor is connected between a positive voltage output of one of the switching regulators and the capacitors. The pair of diodes is connected between the positive voltage output of one of the switching regulators and the negative output rail of the switching regulators.