The custom Maximum Power Point Tracker (MPPT) charges the battery using power from the solar panels. Because the battery charges to 28V, and most of the electronics on the rover use smaller voltages than that, several DC/DC converters from International Rectifier are being implemented. A DC/DC converter is an electronic component that takes in one voltage and converts it to a different voltage. These particular DC/DC converters can take in a wide range of voltages, ranging from 16V to 40V, and produce either 5V, 12V, or a clean 28V. The DC/DC converters will supply clean, consistent, and reduced voltages to the rover’s on board electronics. Because the DC/DC converters have both input and output filters, they ensure very clean voltages for even the rover’s most sensitive electronics. For microprocessor control, these converters also provide an on/off pin as well as a pin providing an analog voltage indicating the current through the device for current monitoring.

All of these features have been bench tested with excellent results, and over the next couple of weeks the DC/DC converters will be mounted on heat sinks and installed into the rover.

Soldering wire leads to pins on DC/DC converter

Leads and capacitor connected

Verifying 12 volt output

Running motor off 12 volt output of DC/DC converter