These buck (step-down) voltage regulators generate lower, user-selectable output voltages from an input voltage range of 4.5 to 24 V. They are switching regulators (also called switched-mode power supplies (SMPS) or DC-to-DC converters) and have a typical (when the output current is several amps) efficiency of approximately 90%, which is much more efficient than linear voltage regulators, especially when the difference between the input and output voltage is large. The output voltage defaults to 5 V and can be changed to 3.3 V by jumping 3V3 SEL.
The regulator has under-voltage and short-circuit protection, and thermal shutdown prevents damage from overheating. The board has reverse-voltage protection.
- input voltage: 4.5 V to 24 V
- typical continuous output current: 3.5 A (Actual continuous output current depends on thermal dissipation. See Output Current section below for details)
- output voltage selectable as 5 V or 3.3 V
- 700 kHz switching frequency
- 15 mA typical no-load quiescent current (150 µA typical quiescent current with EN=0 V)
- integrated over-current shutoff
- small size: 1.68" × 0.46" × 0.3" (43 × 12 × 8 mm)
- weight without header pins: 0.1 oz (3 g)
Using the Regulator