An electronic amplifier, amplifier, or (informally) amp is an electronic device that increases the power of a signal. It does this by taking energy from a power supply and controlling the output to match the input signal shape but with a larger amplitude. Amplifier design relies on feedback mechanism. Offsets that accumulate in different stages of amplifier are corrected by feedback mechanism. ...

A transmitter front-end IC for ultrasound medical imaging applications is implemented using 30-V 0.18-mm Bipolar/CMOS/DMOS process. The proposed ultrasound transmitter front-end, consisting of voltage level-shifters and an output driver, achieves high integration and maintains good reliability while generating a 33 ns output pulse signal in order to drive a large capacitive load, which represen...

ETRI Journal, Volume 29, Number 1, February 2007 A new low-voltage CMOS interface circuit with digital output for piezo-resistive transducer is proposed. An input current sensing configuration is used to detect change in piezo-resistance due to applied pressure and to allow lowvoltage circuit operation. A simple 1-bit first-order deltasigma modulator is used to produce an output digital bitstre...

We present a high bandwidth piezoelectric-actuated mirror for length stabilization of an optical cavity. The actuator displays a transfer function with a flat amplitude response and greater than 135 masculine phase margin up to 200 kHz, allowing a 180 kHz unity gain frequency to be achieved in a closed servo loop. To the best of our knowledge, this actuator has achieved the largest servo bandwi...

Development of efficient and sensitive motion transducers for arrays of nanoelectromechanical systems (NEMS) is important for fundamental research as well as for technological applications. Here, we report a single-wire nanomechanical transducer interface, which relies upon near-field optomechanical interactions. This multiplexed transducer interface comes in the form of a single-mode fiber tap...

High Intensity Focused ultrasound (HIFU) is a non-invasive cancer therapy that makes use of the mainly thermal effects of ultrasound to destroy tissue. In order to achieve reliable treatment planning, it is necessary to characterise the ultrasound source (transducer) and to understand how the wave propagates in tissue and the energy deposition in the focal region. This novel exploratory study i...

A heterodyne interference system is developed for base-lines measurement by using an acoustic optical modulator and a stabilized optical-frequency comb. The temporal coherence interference with the optical-frequency comb happen at discrete positions, where a pair of pulse trains overlaps with each other. An optical delay of the interferometer with a piezo-electric transducer is realized to find...

A novel virus-like particle (TMV-VLP) receptor layer has been integrated with an optical microdisk resonator transducer for biosensing applications. This bioreceptor layer is functionalized with selective peptides that encode unique recognition affinities. Integration of bioreceptors with sensor platforms is very challenging due their very different compatibility regimes. The TMV-VLP nanorecept...

Self-sensing techniques for atomic force microscope (AFM) cantilevers have several advantageous characteristics compared to the optical beam deflection method. The possibility of down scaling, parallelization of cantilever arrays and the absence of optical interference associated imaging artifacts have led to an increased research interest in these methods. However, for multifrequency AFM, the ...

Piezoelectric transducers, long used in the generation and detection of ultrasonic waves, have more recently been the detector of choice for acoustic emission signals. Optical probing methods, however, have several important advantages for acoustic emission studies: (1) they have an inherent broad frequency response, free from mechanical resonances, (2) they do not interfere with the acoustic w...