A low noise Si-CMOS amplifier-multiplexer readout circuit array for imaging applications

A low power low noise CMOS amplifier with integrated filter for neural signal recording is designed and fabricated with CSMC 0.5 μm CMOS process. DC offsets introduced by electrode-tissue interface are rejected through a feedback low-pass filter. The bandwidth of the amplifier is in 3.5Hz-5.5KHz range, and the gain is about 48dB in the midband. AC input differential mode voltage range is 10mV, and DC input differential mode voltage range is 180mV. The amplifier can accommodate 180mV DC offsets drift and 10mV neural spikes. The neural probe array is integrated directly on the surface of the amplifier array chip, and is tested in saline solution, and also is implanted in rats in vivo , the results of the experiments show that the amplifier is suitable for neural signal recording. The power dissipation is about 14μW while consuming 0.16 mm2 of chip area, which satisfies implantable devices requirements.

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A Low Noise Low Offset Readout Circuit for Magnetic-Random-Access-Memory

IEEE Transactions on Circuits and Systems I Regular Papers ◽

10.1109/tcsi.2017.2743045 ◽

2018 ◽

Vol 65 (4) ◽

pp. 1224-1233

Author(s):

Anatoli Mordakhay ◽

Yevgeniy Telepinsky ◽

Lior Klein ◽

Joseph Shor ◽

Alexander Fish

Keyword(s):

Random Access ◽

Random Access Memory ◽

Low Noise ◽

Readout Circuit ◽

Access Memory ◽

Magnetic Random Access Memory ◽

Low Offset

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Magnetoelectric Sensors With Directly Integrated Charge Sensitive Readout Circuit—Improved Field Sensitivity and Signal-to-Noise Ratio

IEEE Sensors Journal ◽

10.1109/jsen.2011.2113333 ◽

2011 ◽

Vol 11 (10) ◽

pp. 2260-2265 ◽

Cited By ~ 9

Author(s):

Zhao Fang ◽

Ninad Mokhariwale ◽

Feng Li ◽

Suman Datta ◽

Q. M. Zhang

Keyword(s):

Room Temperature ◽

Signal To Noise Ratio ◽

Low Noise ◽

Magnetic Sensors ◽

Readout Circuit ◽

Signal To Noise ◽

Low Frequencies ◽

Field Sensitivity ◽

Piezoelectric Layers ◽

Noise Ratio

The large magnetoelectric (ME) coupling in the ME laminates makes them attractive for ultrasensitive room temperature magnetic sensors. Here ,we investigate the field sensitivity and signal-to-noise ratio (SNR) of ME laminates, consisting of magnetostrictive and piezoelectric layers (Metglas and piezopolymer PVDF were used as the model system), which are directly integrated with a low noise readout circuit. Both the theoretical analysis and experimental results show that increasing the number of piezoelectric layers can improve the SNR, especially at low frequencies. We also introduce a figure of merit to measure the overall influence of the piezolayer properties on the SNR and show that the newly developed piezoelectric single crystals of PMN-PT and PZN-PT have the promise to achieve a very high SNR and consequently ultra-high sensitivity room temperature magnetic sensors. The results show that the ME coefficients used in early ME composites development works may not be relevant to the SNR. The results also show that enhancing the magnetostrictive coefficient, for example, by employing the flux concentration effect, can lead to enhanced SNR.

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