Growing interest in the electrical properties of living organisms has required the development of amplifiers sufficiently sensitive and stable to record the minute changes in potential encountered. Such amplifiers must be of high gain, with differential input (so that several amplifiers may be used simultaneously on one specimen), freedom from voltage drift, and should be direct coupled through...

To improve low sense margin at low voltage, we propose a negatively driven sensing (NDS) scheme and to solve the problem of WL-to-BL short leakage fail, a variable bitline reference scheme with freelevel precharged bitline (FLPB) scheme is adopted. The influence of the threshold voltage offset of NMOS and PMOS transistors in a latch type sense amplifier is very important factor these days. From...

Amplifiers employing positive or negative feedback are fundamental building blocks in electronic circuits. Negative feedback is employed to linearize amplifiers in order to reduce distortion of the input signal and improve amplifier bandwidth. Conversely, applying sufficient positive feedback to an amplifier results in an oscillator because an output signal occurs when no input signal is presen...

This work describes a 0.18μm CMOS implementation of an EEG acquisition system with programmable gain amplifier. Gain of the amplifier is digitally programmable from 35.09 dB to 62.55 dB by using 6 bits digital input. EEG input signals are of the range of few micro-voltage. Hence a high gain operational transconductance amplifier with gain of 62.83 dB is designed. Two 22:1 multiplexers with 5 se...

This paper discusses the undesirable charge transfer by the parasitic capacitances of the input transistors in a voltage sense amplifier. Due to its intrinsic rail-to-rail voltage transition, the input sides are inevitably disturbed. It can possible disturb the stabilities of the reference voltage levels. Moreover, it becomes serious in multi-channel systems by altering them for other channels,...

This paper discusses the undesirable charge transfer through the parasitic capacitances of the input transistors in a multi-inputs voltage sense amplifier. Its intrinsic rail-to-rail voltage transitions at the output nodes inevitably disturb the input sides through the capacitive coupling between the outputs and inputs. Then, it can possible degrade the stabilities of the reference voltage leve...

In this paper design for 1 volt rail to rail supply voltage output of operational amplifier with common mode feedback amplifier has been presented. The circuit has been simulated using BSIM4 model with 50nm CMOS process. The simulation results show that output voltages for the modified operational amplifier are swinging from 10mV to 990mV i.e. between the rail to rail supply voltages (0 to 1V)....

A class E power amplifier including coupling coils is proposed for application in a wireless power transfer system using magnetic coupling. The proposed amplifier is directly connected to the coils with no discrete components for harmonic filtering and dc feeding, which could cause efficiency degradation of the amplifier. The system with the differential amplifier shows 6.95 W of transmitted po...

This paper describes an instrumentation amplifier (INA) with three operational amplifier (op amp) topology, for biomedical applications. To achieve low offset new circuit technique is achieved by adding NMOS transistor and two phase clock scheme with a frequency of 20 KHz. With the unity gain bandwidth of 92 KHz , the open loop gain of this instrumentation amplifier is found to be 50 dB and hav...

This paper presents the design and simulation of Low Noise Amplifier (LNA) in a 0.18μm CMOS technology. The LNA function is to amplify extremely low noise amplifier without adding noise and preserving required signal to noise ratio. Cadence design tool Spectre_RF is used to design and simulation based on resistors, inductors, capacitors and transistors. Power constrained methodology is used for...