A fully-integrated servo feedback loop for MICS

Use of wireless transmission of biological data between servers and partners and design of a high quality implantable miniature devices to transmit realtime physiologic parameters (e.g., ECG, EEG, EOG, EMG, Neural, Blood Flow, Blood Pressure, etc.) from a patient body could be the key point in saving the patient's life. Such implantable devices are expected to deliver high level of comfort, mobility, and better patient care. The transceivers in such devices often suffer from DC offset problem which could reduce the overall dynamic range and even saturate systems at high gain levels. Adaptive digital signal-processing techniques along with digital to analog converters (DAC's), which is typically used in wireless communications, may not be adopted in biomedical applications due to power inefficiency. This work proposes utilizing servo feedback loop for DC offset compensation. However, it would require large passive component values that are impractical for integration on a silicon chip. This work proposes the design of fully-integrated servo loop utilizing R-2R ladder networks.