A Micropower Electrocardiogram Amplifier

A Micropower Chopper - CDS Operational Amplifier

A low-power spur-free precision amplifier, which uses input chopping and correlated double sampling for demodulation, is presented. This circuit employs an AC coupling between the first and the second stage that removes the first stage offset without causing ripple. The input rail-to-rail circuit, fabricated in a mixed 0.18–0.5 m CMOS technology, operates with supply ranging from 1.8 V to 5 V. ...

Fast Electrocardiogram Amplifier Recovery after Defibrillation Shock

Abstract: A procedure for fast ECG amplifier recovery after defibrillation shocks was developed and simulated in the MATLAB environment. Exponentially decaying post-shock voltages have been recorded. Signals from the AHA database are taken and mixed with the recorded exponential disturbances. The algorithm applies moving averaging (comb filter) on the compound input signal, thereby obtaining th...

A Novel Monolithic Micropower Amplifier Using a SiGe n-MODFET Device

A micropower-relevant model is extracted from the DC characteristics of an n-type buried channel Si/SiGe HMODFET (Hetero-junction Modulation Doped FET). This model is then used to design a novel monolithic SiGe single-stage class-A power amplifier for micropower operation (sub 500μW). The amplifier is fabricated and measured data of the power-gain versus operating power are presented here for t...

A Micropower Low-Distortion Digital Pulsewidth Modulator for a Digital Class D Amplifier

We describe the design of a micropower digital pulsewidth modulator (PWM) for a hearing instrument Class D amplifier. The PWM embodies a novel delta-compensation ( C) sampling process and a novel pulse generator. The C process is sampled at the same low rate as reported algorithmic sampling processes and it features a similar low total harmonic distortion (THD). Its arithmetic computation is ho...

A micropower chopper-correlated double-sampling amplifier with 2µV standard deviation offset and 37nV/√Hz input noise density