A linearized digital radio frequency (RF) power amplifier (PA), a switched RF PA, is more power efficient than an analog amplifier, but may cause interference in adjacent transmitting channels similar to analog amplifiers. This interference is due to the inherent nonlinearities, and this project investigated the possibility of reducing this interference by using a prefilter, a predistorter, to ...

A new MOS-C bandpass-low-pass filter using the current feedback operational amplifier (CFOA) is presented. The filter employs two CFOA’s, eight MOS transistors operating in the nonsaturation region, and two grounded capacitors. The proposed MOS-C filter has the advantage of independent control of Q and !o. PSpice simulation results for the proposed filter are given.

For low-voltage, low-power circuit design, the linear model for operational amplifiers is insufficient to accurately predict the static and dynamic behavior of the circuit. This paper introduces a nonlinear model for operational amplifiers based on amplifiers’ DC transfer characteristic. By using this nonlinear model, the behavior of an operational amplifier with feedback network can be describ...

To perform correct measurements on a true digital audio amplifier (TDAA), it is important to understand the characteristics of the device, especially in comparison with conventional linear amplifiers such as class-A and class-AB. This report provides an overview of TI’s proprietary digital amplification technology and information about how measurements on TDAA’s must be performed in order to ob...

Audio amplifier servicing is one of the competencies to acquire electronic product assembly and skills. The students taking this course found difficulties in learning basic troubleshooting an audio because absence available materials for hands-on experience understanding essential servicing. It inspired researcher develop trainer through research development improve knowledge skills simulation ...

Tammes, A. An electronic device which automatically halves "off-sca'.e" signal voltages of the SMA 12/60 is described. Presetting permits any electronic dilution desired. It may be constructed from commercial components by a reasonably proficient electronic technician. The device is placed "in-line" at the terminal box of the recorder without further modification of the SMA 12/60. It senses and...

The combined effects of deviation from ideal in integrator upon the characteristics of the integrators. Inverting and noninverting magnitude and phase on the performance of integrator-based active filters integrators for use in active filters which are independent of first-order and is investigated. The limitations of using the integrator Q-factor as a second-order operational amplifier time co...

Introduction Scattering of optical radiation by materials is a topic that has received much attention over the past 100 years. One particular type, Raman scattering, was first observed by C.V. Raman in 1928, and since then this inelastic scattering process has found many uses in basic and applied science. Raman scattering can be used to make spectroscopic measurements, or exploited to build Ram...

This dissertation discusses the theory of single-amplifier biquadratic filters (SABs) and their implementation as CMOS video-frequency filters. It shows that building filters as cascades of single-amplifier biquadratic MOSFET–C sections is a viable alternative to using biquadratic Gm–C filter sections. The advantage of MOSFET–C SABs is that they typically use less chip area than a Gm–C filter w...

This note describes a number of techniques that can be used to detect low level optical signals. It starts by considering the problems inherent in the use of DC techniques and how these may be reduced by using AC methods instead. It then discusses a range of different experimental approaches using lock-in amplifiers, pointing out the advantages as well as any disadvantages of each method. Final...