Arduino LM2577 DC-DC Adjustable Step-up Power Converter Module . The LM2577 series of regulators are monolithic integrated circuits that provide all the active functions for a step-up(buck) switching regulator, capable of driving a 3A load withexcellent line and load regulation. This module uses the adjustable output version, it would facilitate your application and be your good assistant in your debugging.
Features
Module Properties: Non-isolated buck Module
Rectification: Non-synchronous rectification
Input voltage: 3V-34V
Output voltage: 4-35V(The output voltge must be higher than the input votage)
Input Current: 3A (MAX)
Output Current: 2.5A (MAX)
Module size: 49 (mm) x26 (mm)
Input: 'IN+' input is Positive, 'IN-' type negative
Output: 'OUT+' output is Positive, 'OUT-' type negative