Datasheet

This flexibility in input voltage is especially well-suited for battery-powered applications in which the
battery voltage begins above the desired output voltage and drops below the target as the battery
discharges. Without the typical restriction on the battery voltage staying above the required voltage
throughout its life, new battery packs and form factors can be considered. For example:
• A 4-cell battery holder, which might have a 6 V output with fresh alkalines or a 4.0 V output with
partially discharged NiMH cells, can be used with this regulator to power a 5 V circuit.
• A single lithium-polymer cell can run a 3.3 V device through its whole discharge cycle.
• A disposable 9 V battery powering a 5 V circuit can be discharged to under 3 V instead of cutting out
at 6 V, as with typical linear or step-down regulators.
In typical applications, this regulator can deliver up to 1 A continuous when the input voltage is higher
than the output voltage (stepping down). When the input voltage is lower than the output voltage
(stepping up), the available current decreases as the difference between the voltages increases; please
see the graphs at the bottom of this page for a more detailed characterization. The regulator has short-
circuit protection, and thermal shutdown prevents damage from overheating; the board does not have
reverse-voltage protection.
Features
• Input voltage: 2.7 V to 11.8 V
• Output voltage adjustable from 2.5 V to 8 V
• Typical continuous output current: 500 mA to 1 A across most combinations of input and output
voltages (Actual continuous output current depends on input and output voltages. See Typical
Efficiency and Output Current section below for details.)
• Power-saving feature maintains high efficiency at low currents (quiescent current is less than 0.3 mA)
• Integrated over-temperature and short-circuit protection
• Small size: 0.45″ × 0.65″ × 0.1″ (11 × 17 × 3 mm)
Using the Regulator
During normal operation, this product can get hot enough to burn you. Take care when handling this
product or other components connected to it.