Pololu 3.3V Step-Up Voltage Regulator U1V10F3

This 3.3 V boost (step-up) voltage regulator generates higher output voltages from input voltages as low as 0.5 V, and it also automatically switches to a linear down-regulation mode when the input voltage exceeds the output. This makes it great for powering 3.3 V electronics projects from 1 to 3 NiMH, NiCd, or alkaline cells or from a single lithium-ion cell.

When boosting, this module acts as a switching regulator (also called switched-mode power supplies (SMPS) or DC-to-DC converters) and has a typical efficiency between 65% to 85%. The available output current is a function of the input voltage, output voltage, and efficiency (see Typical Efficiency and Output Current section below), but the input current can typically be as high as 1.2 A. This regulator is also available with a fixed 5 V output, and very similar 3.3V, 5V, and adjustable-output versions are available with a true shutdown option that turns off power to the load.

The regulator’s thermal shutdown engages at around 140°C and helps prevent damage from overheating. It does not have built-in protection against reverse voltage, but reverse-voltage protection modules are available for adding that functionality.

• Input voltage: 0.5 V to 5.5 V
• Fixed 3.3 V output with 4% accuracy
• Automatic linear down-regulation when the input voltage is greater than the output voltage
• 1.2 A switch allows for input currents up to 1.2 A
• Good efficiency at light load: