This paper presents a compact DDA-based fully-differential CMOS instrumentation amplifier dedicated for micro-power ECG monitoring Only eight transistors are employed to realize a power-efficient current-sharing DDA A RC network (using MOS pseudo resistors and poly capacitors) forms feedback loops around the DDA creating an ac-only amplification The proposed amplifier is dc-coupled via gate terminals of the p-channel input transistors It thus achieves sufficiently high input impedance over the entire ECG frequency range Fabricated in a 035-μm CMOS process, the proposed amplifier occupies 00712 mm2 It operates from a 2 V dc supply with 336 nA current consumption Measurements show that the amplifier attains its input impedance of 575 MΩ at 150 Hz and achieves 154 μVrms input-referred noise over 01-300 Hz Noise and power efficiency factors are 202 and 816, respectively At 50 Hz, the mean CMRR of 8324 dB is obtained from 11-chip measurement Experiments performed on a human subject confirm the functionality of the proposed amplifier in a real measurement scenario

A Compact Sub-μW CMOS ECG Amplifier With 57.5-MΩ Z in , 2.02 NEF, 8.16 PEF and 83.24-dB CMRR

Design of ECG Front End Amplifier Based on CMOS OTA

A programmable analog front-end with independent biasing technique for ECG signal acquisition

Heart disease has always been a threat to people's health throughout the world and is regarded as a global non-infectious disease. Heart aging is an inevitable natural law, cardiovascular diseases peaks into an aging trend, additionally, teenagers who do not pay attention to health care may also suffer from it. So, electrocardiogram (ECG) monitoring has been increasingly more and more vital in modern medical diagnosis, and it has great potential for future development. The article gave the readers insights into two core components of the ECG wearable device, the most cutting-edge technic. The following topics are discussed: electrodes and ECG front-end circuits. Two kinds of dry electrodes and electrocardiogram amplifiers were particularly introduced and some backgrounds were illustrated as well. The article is meaningful, it described the latest research on ECG monitoring, and these introductions can be used as references for more cardiac medical personnel.

Readout front-end for wearable ECG

This paper describes and compares three amplifiers for ECG recording, namely a four-transistor stage band-pass amplifier, a DDA-based fully differential CMOS instrumentation amplifier and an OTA amplifier using current reuse. The performance metrics of the three amplifiers are listed, their respective advantages are compared, what factors limit their disadvantages are analyzed, the current state of the art and the direction of development of the ECG amplifier are indicated, and suggestions are given for further enhancement of the ECG amp. These amplifier circuits are designed in 0.35 µm CMOS and are verified by layout followed by simulation simulations. The results show that running at 2V dc supply, the quad-transistor stage amplifier and the DDA fully differential amplifier consume 672nW, obtain at least 2uVrms of input reference noise, and obtain greater common mode rejection ratios of 86dB and 83dB, while the OTA amplifier consumes less 320nW, obtains the most 2.05uVrms of input reference noise, and obtains a smaller common-mode rejection ratio of 65dB.

Current state and challenges of ECG amplifiers

This paper describes a differential CMOS bandpass amplifier dedicated for ECG acquisition. The proposed amplifier is constituted by a current-feedback instrumentation amplifier made from only 4 transistors in conjunction with capacitive-resistive feedback network. The amplifier circuit was designed using 0.35 micron CMOS and verified by post-layout simulation. It shows that the proposed amplifier provides 40 dB and 0 dB mid-band and dc amplifications, respectively. The amplifier bandwidth acquires 0.1 to 279 Hz. The input referred noise and input impedance of 2 μV rms and 295 MΩ (at 50 Hz) are obtained. Monte-Carlo mismatch simulation confirms the amplifier's common-mode rejection ratio of 77 dB. Operated from a 2 V dc supply, the ECG amplifier consumes 672 nW.

A 0.672 μW, 2 μV rms CMOS Current-Feeback ECG Pre-amplifier With 77 dB CMRR

This paper is a part of designing a volume catheter monitor using conductance techniques. An electronic instrument has been constructed for real-time blood volume monitoring during the cardiac cycle. Results show how possible to design and construct electric current driver and voltage measuring circuits via electrodes of a conductance catheter for blood volume measurement.

To investigate how to design electric current driver and voltage measuring circuits of a conductance catheter for blood volume measurement

This paper presents the design of a CCII-based electrocardiogram (ECG) amplifier for ECG measurement using two second generation current conveyors (CCII) and five passive devices. An ECG amplifier is proposed in term of compact circuit and DC suppression for ECG measurement. The proposed circuit has the ability to suppress DC and out of band high frequency interference. The proposed circuit was simulated using a commercially available current conveyors AD844 and tested by PSPICE program. The simulation results show that the proposed amplifier attains a mid-band gain of 46 dB, Common Mode Rejection Ratio (CMRR) of 57.76 dB at 10 Hz, and input referred noise is 1.62 μVrms and the dynamic range is 66.78 dB, respectively.

Panlop Pantuprecharat

Papers

A 0.672 μW, 2 μV rms CMOS Current-Feeback ECG Pre-amplifier With 77 dB CMRR

To investigate how to design electric current driver and voltage measuring circuits of a conductance catheter for blood volume measurement

A CCII-Based Electrocardiogram Amplifier with DC Suppression