In my thesis I present a variable bandwidth digital output filter for biomedical application. This circuit is able to gain, filter and digitalize the signals from heart's pacemaker system and carry the digital signals towards signal processing system.
My goal was to develop an implantable integrated circuit, which can meet the requirement of biomedical application like low power consumption and small size. The main power supply is an electrochemical power source therefore low current consumption is very important to increase battery life.
With information about requirements I designed an analog front-end stage, which uses small capacitances to provide low cutoff frenquency adjustable in four steps. The amplifiers in circuit are developed to fulfil application-specific conditions. The filter outputs are adapted to drive the analog-digital converter inputs.
Finally, the results of the simulations able to appoint the most important properties of the application-optimized circuit are presented, and I proposed a possible future research direction.