This paper proposes a simple PID autotuning technique for digitally controlled DC-DC boost converters using the relay feedback technique. Controller parameter tuning is obtained introducing small perturbations on the output voltage by including a relay in the control feedback and ensuring closed-loop operation during the autotuning procedure. Moreover, including the PID regulator in the relay feedback loop, the controller parameters are directly tuned according to the specified dynamic requirement. The proposed algorithm is simple, it requires small tuning times and it is fully compliant with the cost/complexity constraints of integrated digital ICs. Simulation results and experimental results confirm the validity and effectiveness of the proposed solution
