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Abstract: This paper describes the design and implementation of a self-tuning inductive powering system conceived for biomedical applications. The circuit operates at 1MHz and delivers 380 mW to the implant with an efficiency of 50%, at a distance of 1cm. Absorption modulation is used to monitor the circuit parameters allowing the system to deal with distance increases up to 5cm as well as small coil misalignments. The automatic-tuning system adjusts the configuration of the coil driver depending on the self-monitored coupling, acting on a bank of switchable capacitors with a pattern defined by the received data. It is demonstrated that the implemented tuning strategy boosts the transmitted power by a factor two. In addition, the combination of tuning and smart power regulation was proven to sensibly increase the system efficiency by maintaining a constant energy level at the secondary. [Copyright &y& Elsevier]