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Voltage Regulator

Voltage RegulatorThe voltage received from a power source may vary for a number of reasons; the utility voltage may vary with the time of day or weather conditions, or voltage drops in the wiring within a building may vary due to changes in the power demand. In addition, changes in the current drawn by the load being powered will result in varying voltage drops in the wiring between the power source connection and the load, resulting in the load receiving a reduced and varying voltage.

The voltage regulator portion of a power supply provides a constant output voltage to the load by compensating for all of the factors tending to influence it. The voltage regulator circuitry monitors its output voltage with a feedback path and continuously adjusts its operating point as required to keep the power supply's output stable at its set point regardless of changes in the input voltage. This is referred to as line regulation. And by using additional wires (‘sense leads’) to extend the feedback path of the power supply's voltage regulator to the load instead of just to the power supply’s output terminals, the voltage regulator will also compensate the voltage drops in the wiring to the load (‘load regulation’).