A Gate-Leakage Insensitive 0.7-V 233-nW ECG Amplifier using Non-Feedback PMOS Pseudo-Resistors in 0.13-μm N-well CMOS

A fully-differential low-voltage low-power electrocardiogram (ECG) amplifier by using the nonfeedback PMOS pseudo-resistors is proposed. It consists of two operational-transconductance amplifiers (OTA) in series (a preamplifier and a variable-gain amplifier). To make it insensitive to the gate leakage current of the OTA input transistor, the feedback pseudo-resistor of the conventional ECG amplifier is moved to input branch between the OP amp summing node and the DC reference voltage. Also, an OTA circuit with a Gm boosting block without reducing the output resistance (Ro) is proposed to maximize the OTA DC gain. The measurements shows the frequency bandwidth from 7 ㎐ to 480 ㎐, the midband gain programmable from 48.7 ㏈ to 59.5 ㏈, the total harmonic distortion (THD) less than 1.21% with a full voltage swing, and the power consumption of 233 ㎻ in a 0.13 ㎛ CMOS process at the supply voltage of 0.7 V.

[1]  Refet Firat Yazicioglu,et al.  A 60 $\mu$W 60 nV/$\surd$Hz Readout Front-End for Portable Biopotential Acquisition Systems , 2007, IEEE Journal of Solid-State Circuits.

[2]  Yong Lian,et al.  A 1-V 450-nW Fully Integrated Programmable Biomedical Sensor Interface Chip , 2009, IEEE Journal of Solid-State Circuits.

[3]  Young-Hee Kim,et al.  Design of an EEPROM for a MCU with the Wide Voltage Range , 2010 .

[4]  Juha Kostamovaara,et al.  A 1-V analog CMOS front-end for detecting QRS complexes in a cardiac signal , 2005, IEEE Transactions on Circuits and Systems I: Regular Papers.

[5]  K. Leung,et al.  A capacitor-free CMOS low-dropout regulator with damping-factor-control frequency compensation , 2003, IEEE J. Solid State Circuits.

[6]  R. R. Harrison,et al.  A low-power low-noise CMOS amplifier for neural recording applications , 2003, IEEE J. Solid State Circuits.

[7]  Chuan Yi Tang,et al.  A 2.|E|-Bit Distributed Algorithm for the Directed Euler Trail Problem , 1993, Inf. Process. Lett..

[8]  W. J. Tompkins,et al.  Estimation of QRS Complex Power Spectra for Design of a QRS Filter , 1984, IEEE Transactions on Biomedical Engineering.

[9]  Gregory T. A. Kovacs,et al.  A multiparameter wearable physiologic monitoring system for space and terrestrial applications , 2005, IEEE Transactions on Information Technology in Biomedicine.

[10]  Sungmee Park,et al.  Enhancing the quality of life through wearable technology , 2003, IEEE Engineering in Medicine and Biology Magazine.