Power supply module with an input voltage from 6 to 12 V and a configurable output voltage of 3.3 V or 5 V. It has holes with a 2.54 mm pitch. Perfect for use with a breadboard. SparkFun PRT-13032

Step-Down DC-DC converter module based on the D24V150F12 chip. Input voltage 14.5 ... 40V, output voltage 12V (max 15A). Pololu 2885

The compact (0.4″ × 0.5″) D24V5F15 synchronous buck voltage regulator takes an input voltage of up to 36 V and efficiently reduces it to 15 V while allowing for a maximum output current of 500 mA. Pololu 2847

Pololu 6V Step-Up Voltage Regulator U3V50F6

Pololu 9V Step-Up Voltage Regulator U3V50F9

The Step-UpU1V11A Buck Voltage Regulator module with adjustable output voltage 2-5.25V, input voltage range of 0.5-5.5V and a maximum output current of 1.2A. Pololu 2560

The Step-Up/Step-DownS7V8A Buck Voltage Regulator module with adjustable output voltage in range of 2.5-8V, input voltage range of 2.7-11.8V and a maximum output current of 0.5-1A. Pololu 2118

The energy harvesting module based on the LTC3588 chip, which is a complete energy harvesting solution for sources such as piezoelectric, solar or magnetic transducers. SparkFun BOB-09946

The Step-Down D24V3AHV Buck Voltage Regulator module with adjustable output voltage in the range of 4-25V with a wide input voltage range of 4.5-42V and a maximum output current of 300 mA. Pololu 2102

Step Down converter module with an output voltage of 5 V and a maximum current of 3 A. The board is equipped with two USB connectors

DC-DC step-up/step-down voltage regulator module that stabilizes the output voltage at 9 V with an input voltage range of 2,9 V – 32 V. The circuit automatically increases or decreases the input voltage, allowing it to power devices even when the supply voltage varies significantly. The regulator can deliver up to 2 A output current (when the input voltage is close to the output voltage) and offers a typical 80–90% efficiency, making it suitable for battery-powered systems and embedded projects. Pololu 2576

Step-Down converter with an output voltage of 5 V, input voltage from 4.5 to 40 V and a maximum current of 2 A. The board is equipped with a segment LED display and a USB output

Step-Down converter D36V50F3 with an output voltage of 3.3 V, an input voltage from 4.5 to 50 V and a maximum output current of 9.5 A. Pololu 4090

The Step-Up Buck Voltage Regulator module with adjustable output voltage in range of 2.5-9.5V with a input voltage range of 1.5-16V and a maximum output current of 2A. Pololu 791

Step-Up/Step-Down converter with an output voltage of 3.3 V, an input voltage from 3 to 15 V and a maximum current of up to 600 mA

This synchronous switching step-down (or buck) regulator takes an input voltage of up to 38 V and efficiently reduces it to 5 V with an available output current of around 9 A.

Step-up DC-DC converter module based on the LM2587 circuit, input voltage 3.5..30V, regulated output voltage 4..30V. The module is equipped with ARK connectors

Przetwornica DC-DC Step Down (MP1584), Uwe 4.5..28V, Uwy regulowane 0.8..20V, RoHS

The Step Down DC-DC converter module (MP2307) allows to obtain 0.93..18V output voltage at 4.75..24V input voltage. The output voltage is regulated by a potentiometer

Pololu 2832