Haptics, like the fields of robotics and motion control, relies on high stiffness position control of electric motors. Traditionally DC motors are driven by current amplifiers and encoder-based position feedback creates virtual springs. Unfortunately, sensor quantization, discretization, and amplifier bandwidths impose performance limits, while the amplifiers work hard to cancel the motor’s ele...

An active-feedback frequency-compensation (AFFC) technique for low-power operational amplifiers is presented in this paper. With an active-feedback mechanism, a high-speed block separates the low-frequency high-gain path and high-frequency signal path such that high gain and wide bandwidth can be achieved simultaneously in the AFFC amplifier. The gain stage in the active-feedback network also r...

This paper reviews optical fiber amplifiers such as Erbium doped fiber amplifiers EDFAs, many types of Raman amplifiers RAs, Thulium doped fiber amplifiers, Tellurite-based fiber Raman amplifiers, semiconductor optical amplifiers and fiber optic parametric amplifiers, principle of operation and construction. As these amplifiers are used for optical fiber communication projects so we shall go th...

Heterojunction bipolar transistors (HBTs) extend the advantages of silicon bipolar transistors to significantly higher frequencies. They are used in applications requiring high current capacities, high transconductance, high voltage handling capability, low noise and uniform threshold voltage [1]-[2]. The InGaP/GaAs HBT is an important investigation topic in power amplifiers [3]-[4], but the te...

III.1. Basic Model for the Operational Amplifier. The OPerational AMPlifier (OPAMP) is a key building block in analog integrated circuit design. The OPAMP is composed by several transistors and passive elements (resistors and capacitors) and arranged such that its low frequency voltage gain is very high; the dc gain of the OPAMP-741 is around 10 V/V (10 μV at the input give us 1 V at the output...

In this paper a new high gain bandwidth (GBW) and low power folded cascade OPAMP is presented. It has been implemented and layouted by CADENCE software in 0.18μm. Its DC gain is 82db and its bandwidth is 200MHz. Power consumption is one of the main design challenges in very-lowvoltage high-speed analog integrated circuits. In this paper, different techniques to reduce the power consumption in l...

Haptic rendering commonly implements virtual springs using DC motors with current amplifiers and encoder-based position feedback. In these schemes, quantization, discretization, and delays all impose performance limits. Meanwhile the amplifiers try to cancel the electrical motor dynamics, which are actually beneficial to the haptic display. We present an alternate approach that fully embraces a...

Chauhan, Shweta. M.S.Egr, Department of Electrical Engineering, Wright State University, 2014. Hysteretic controlled DC-DC converters. Switched-mode DC-DC converters are widely used in applications requiring stepup and step-down of DC voltages or currents. These converters find their use in portable applications such as laptops and smart phones, radio-frequency power amplifiers, as light emitti...

A fully differential Miller op-amp with a composite input stage using resistive local common-mode feedback and regulated cascode transistors is presented here. High gain pseudo-differential auxiliary amplifiers are used to implement the in order boost output impedance of open-loop op-amp. Both stages operate class AB mode. The proposed has been simulated 130nm commercial CMOS process technology...