Step-Up DC-DC Converter Calibration and Adjustment Using a Digital Potentiometer


The purpose of this application note is to show an example of how a digital potentiometer can be used in the feedback loop of a step-up DC-DC converter to provide calibration and/or adjustment of the output voltage. The example circuit uses a MAX5025 step-up DC-DC converter (capable of generating up to 36V, 120mW max) in conjunction with a DS1845, 256 position, nonvolatile (NV) digital potentiometer. For this example, the desired output voltage is 32V, which is generated from an input supply of 5V. The output voltage can be adjusted in 35mV increments (near 32V) and span a range wide enough to account for resistance, potentiometer and DC-DC converter tolerances (27.6V to 36.7V). Read full article.