A low-dropout regulator (LDO regulator) is a DC linear voltage regulator that can regulate the output voltage even when the supply voltage is very close to the output voltage. The advantages of an LDO regulator over other DC-to-DC voltage regulators include the absence of switching noise (as no switching takes place), smaller device size (as neither large inductors nor transformers are needed), and greater design simplicity (usually consists of a reference, an amplifier, and a pass element). The disadvantage is that, unlike switching regulators, linear DC regulators must dissipate power, and thus heat, across the regulation device in order to regulate the output voltage