Ultra small DC DC 0.8 3.3V to DC 3.3V Step UP Boost PFM Voltage Converter Power Supply Module DC/DC 1.5V 2V 2.5V 3V for DUE FPGA|module bluetooth|module amplifiermodule gsm - AliExpress
Pololu 3.3V Step Up Down Voltage Regulator
DC-Buck-Booster-Step-Up-Down : DC DC Automatic Step Up-down ...
Pololu 3.3V Step-Up/Step-Down Voltage Regulator S7V8F3 | POLOLU-2122 | Core Electronics Australia