This powerful step-up/step-down regulator efficiently produces an adjustable 9 V to 30 V output from input voltages between 3 V and 30 V while allowing a typical output current of up to 2 A when the input voltage is close to the output voltage and offering typical efficiencies of 80% to 90%. Its ability to convert both higher and lower input voltages makes it useful for applications where the power supply voltage can vary greatly, as with batteries that start above but discharge below the regulated voltage.
These step-up/step-down regulators take an input voltage from 3 V to 30 V and increase or decrease it as necessary to produce an adjustable 9 V to 30 V output, depending on the version. They are switching regulators (also called switched-mode power supplies (SMPS) or DC-to-DC converters) with a single-ended primary-inductor converter (SEPIC) topology, and they have a typical efficiency between 80% and 90%. The available output current is a function of the input voltage, output voltage, and efficiency (see the Typical Efficiency and Output Current section below), but it will be around 2 A when the input voltage is close to the output voltage.
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