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Neural Amplifier Circuits in Implants

  • Vinod Kumar Khanna
Chapter

Abstract

The neural signals are low-frequency (mHz–kHz) and low-amplitude signals (μV–mV). Therefore, the amplifiers for these signals must be low-noise circuits. Additionally, the front-end amplifiers must reject interference due to the common-mode signals as well as electrode effects. Amplification techniques based on clocking and continuous-time approaches are described. The clock-based techniques include switched-biasing, chopper and auto-zeroing methods. The traditional continuous-time circuit is the AC-coupled-operational transconductance amplifier based neural amplifier endowed with capacitive feedback. The unavoidable tradeoff between input capacitance and area of the chip against the gain of the amplifier can be relaxed. This is achieved when a clamped T-capacitor network replaces the feedback capacitor.

Keywords

Neural amplifier Biopotential amplifier Switched-bias amplifier Chopper-stabilized amplifier Auto-zeroing amplifier Continuous-time amplifier Zero-drift amplifier IMD Operational transconductance amplifier 

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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Vinod Kumar Khanna
    • 1
  1. 1.CSIR-Central Electronics Engineering Research InstitutePilaniIndia

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