Time is always a critical factor for these circuits. Changing the voltage level too early or too late can result in the inefficient performance of the device or even malfunctions. In most converters, everything is controlled by hardware, and response time takes no longer than microseconds. Analog DC-DC converters modules are simple but perform well enough.
However, in some cases, electronics development companies may decide to use microcontrollers in the design of DC-to-DC converters.
When there’s a need to DWE control many parameters (in complex battery management systems, for instance), this function can be implemented with a microcontroller. It provides better flexibility in the realization of control algorithms. For example, in inverter welding machines, you need to control the power keys and the output voltage and also measure the output current. The device has different operating modes, including the one designed for working under the conditions of increased humidity. This mode requires reducing the output voltage to not exceed 30 V.
In such cases, the control functions can be handed over to a microcontroller. Microcontrollers fulfill the following functions:
1. House-keeping to ensure proper work of a DC-DC converter.
2. Parameter setting that implies dynamic control over the output voltage or current, etc.
3. Generating control signals for transistors.
In such converters, almost all functions are managed through code. Therefore, it’s very important to properly organize the firmware structure and thus provide the highest speed possible. The microcontroller’s tasks can be divided into two types: time-critical, such as loop control, ADC measurements, system protection, state machine; and non-time-critical, such as fault logging, PMBus or universal asynchronous receiver/transmitter communication, etc.
Thus, the firmware can also be divided into two parts: one that takes care of time-critical tasks (the interrupt loop) and one that controls non-time-critical tasks (the background loop).