Buck converters

The buck converters are used to generate a given output voltage that can be used to e.g. charge batteries (or even control the speed of a DC motor). Since the choice of components for the buck converter determines the maximum output voltage and current three different buck-converters are included in the BC100 design. This can give the application designer an idea of what kind of PCB size that should be expected depending on the desired output voltage and current.

At set of jumpers are used to select which of the three buck converter circuits that are used (refer to jumper section for jumper settings): these connect the board supply to one of the buck converter circuits, connect the ATtiny PWM output to the switching FET, and the output from the buck converters to the battery (through shunt and relays). Refer to Figure 3-1 to see the buck converter designs.

Figure 1. The three buck converters of the BC100 (section of the BC100 schematics).