Tindie Blog | Controlled DC-DC Step Up Converter

If you’re working on some kind of data logging device it can be frustrating if a single sensor needs a different voltage from the rest of the system. The solution is often to have a DC-DC converter but having that running all the time can dramatically decrease your available power budget. This Controlled DC to DC PCB kit takes an off-the-shelf DC-DC converter and adds control functionality allowing the supply to be turned on and off only when needed.

The DC-DC aspect of the kit is a standard pre-built MT3608 module which can receive an input voltage between 2 and 24V and the step-up conversion can output up to 28V. The module sits on top of a custom PCB which is supplied with all the SMD components fitted. The custom PCB uses a P-channel MOSFET switch design to turn on and off the supply voltage to the MT3608 module. You can dial in the output voltage required using the trim pot on the MT3608 and a multi-meter and then you are set up to use a GPIO pin to toggle power to your sensors.

Over on the project page, The Curious Electric Company explain that they needed this for a solar-powered project that was data logging using some 24V sensor once every ten minutes. With the addition of this board, they were able to minimise the time the 24V system was on to around 500ms every 10 minutes. This dramatically reduces the power requirements compared to having the 24V sensors continuously powered.

It looks like a pretty straightforward build with only the through-hole components needing assembly, as such it would be a pretty easy kit for those newer to soldering. There are clear instructions via the documentation link on the product page. The instructions even include an option to bridge a pair of pads to enable a power output LED indicator, but drawing that additional 20-40mA or so might defeat the power-saving objectives of this board!