Recently, Interleaved Boost Converters (IBCs) were one of the most helpful breakthroughs in DC-to-DC voltage boost applications for large power. Despite the many benefits of this topology, the multi-phase concept has its own difficulties in terms of controller design and implementation. The methods used for controller design in brief are literature review, simulation tool selection, model design, testing, analysis, and report. This research presents an alternative controller design to ease the implementation. A single op-amp PI controller is proposed to maintain the voltage stability of the IBCs output. There are three tests to determine the performance of the designed controller. The first test is by providing a constant input voltage and load. The second test is done by changing the load value with a constant input voltage. The next is by changing both the input voltage and the load. Based on the test results, with variations in load and input voltage, the performance of the converter with the proposed controller remains stable, characterized by a steady state error close to 0 in a limited time.