Programmable DC/DC

One of the ideas I am playing around with is to make my own programmable DC/DC PSU based on a MCU. The technique is very similar to a driver channel on a motor by generating a PWM signal. To get a DC out you add filter(s). If you have 48V and 50% PWM duty the output should be 24V etc. The advantages of doing this is that I can switch PSU’s on/off, monitor system currents and use the same module for 5V, 12V, 24V and 48V. And with some of the SO8 MOSFET’s I have used I can deliver 10-15A from a Hat size PSU. I also get the advantage that I can deliver multiple voltages from one input Source and Control how I ramp up/Down Power in a system.

I have done the experiment with the motor drivers, so I know this will work. My main concern is the space needed for capacitors and coils for 10A.

The illustration above also show a PSU line with a relay and current sensor. It is also an option to simply have 3-4 relays, current sensors and capacitance to control power delivered from external modules. The advantage of this is that I can just buy 3rd party PSU’s and plug them in, but it will require a bit more space.

It would most definitively make an interesting project as we also could add programmable output curves like a low frequency function generator.

Space is a concern because I need to take into account that I am driving motors, so we need output capacitance and protection. It might be that a Hat size format is out of the question both due to size and height requirements for the components I will need.

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