Reconfigurable Ferroelectric Bandpass Filter With Low-Frequency Noise Analysis for Intracardiac Electrogram Monitoring

Implantable cardioverter defibrillators (ICDs) provide real-time monitoring and immediate defibrillation for life-threatening arrhythmias. However, the intracardiac electrogram (IEGM) acquisition of ICDs faces stringent constraints, including power consumption, low-frequency noise, and patient-specific physiological variability. This paper introduces an ultra-low-power, high-resolution, reconfigurable three-stage bandpass filter designed specifically for IEGM, utilizing Ferroelectric Field Effect Transistor (FeFET) technology provided by a foundry platform. By employing adjustable threshold voltage V<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> and gate capacitance of FeFET as programmable pseudo-high-value resistors (PHVRs) and capacitor structures, the filter enables personalized cardiac signal isolation tailored to individual patient needs. Additionally, this work incorporates, for the first time, a comprehensive low-frequency noise model covering the entire operational region of FeFET into circuit-level analysis. Based on GlobalFoundries (GF) 28 nm SLPe FeFET-enabled process, the proposed filter achieves a wide gain tuning range (17–77 dB) and a flexible bandwidth tuning range (0.5–19 Hz for low cut-off frequency; 23–138 Hz for high cut-off frequency), with an average power consumption of 257 nW and minimum 11 μV resolution.