Programmable Gain Amplifiers with DC Suppression and Low Output Offset for Bioelectric Sensors

Programmable Gain Amplifiers with DC Suppression and Low Output Offset for Bioelectric Sensors

DC-offset and DC-suppression are key parameters in bioelectric amplifiers. However, specific DC analyses are not often explained. Several factors influence the DC-budget: the programmable gain, the programmable cut-off frequencies for high pass filtering and, the low cut-off values and the capacitor blocking issues involved. A new intermediate stage is proposed to address the DC problem entirel...

Quantum dot amplifiers with high output power and low noise

All CMOS Low-Power Wide-Gain Range Variable Gain Amplifiers

Two variable gain amplifiers (VGAs) that adopt new approximated exponential equations are proposed in this paper. The dB-linear range of the proposed VGAs is extended more than what the approximated exponential equations predict by a bias circuit technique that adopts negative feedback. The proposed VGAs feature wide gain variation, low-power, high linearity, wide control signal range, and smal...

Dc Offset Suppression in Double Balance Direct Conversion Receivers

The double balance mixer scheme in-phase signal input and double-quadrature Local Oscillator (LO) is suggested for application on IQ direct conversion receivers. The influence of the gain and phase mismatches of splitters is investigated. It is shown that a similar scheme using square-law detectors is promising on optical applications. Introduction The increasing interest in direct conversion r...

Time-Domain Response of ECG Bioelectric Amplifiers

This paper investigates the low-frequency response of a multi-stage bioelectric amplifier intended for use in the measurement of the electrocardiogram (ECG) using dry contact electrodes. These electrodes have an impedance which is typically an order of magnitude greater than that of the standard disposable self-adhesive electrodes used in clinical ECG recording. The design was undertaken with t...