internal input impedance
61Quartz crystal microbalance — A quartz crystal microbalance (QCM) measures a mass per unit area by measuring the change in frequency of a quartz crystal resonator. The resonance is disturbed by the addition or removal of a small mass due to oxide growth/decay or film… …
62Parasitic oscillation — is an undesirable oscillation caused by feedback. The problem occurs notably in RF [1], audio, and other electronic amplifiers[2] as well as in digital signal processing.[3] It is one of the fundamental issues addressed by control theory.[4] …
63Database — A database is an organized collection of data for one or more purposes, usually in digital form. The data are typically organized to model relevant aspects of reality (for example, the availability of rooms in hotels), in a way that supports… …
64Signal integrity — or SI is a measure of the quality of an electrical signal. In digital electronics, a stream of binary values is represented by a voltage (or current) waveform. Over short distances and at low bit rates, a simple conductor can transmit this with… …
65iPod — The current iPod line; from left to right: iPod Shuffle, iPod Nano, iPod Classic, iPod Touch …
66Bridged and paralleled amplifiers — Multiple electronic amplifiers can be connected such that they drive a single floating load (bridge) or a single common load (parallel), to increase the amount of power available in different situations. This is commonly encountered in audio… …
67Guitar amplifier — Mesa Boogie Mark IV, a guitar combo amplifier A guitar amplifier (or guitar amp) is an electronic amplifier designed to make the signal of an electric or acoustic guitar louder so that it will produce sound through a loudspeaker. Most guitar… …
68Current-feedback operational amplifier — Representative schematic of a current feedback op amp or amplifier. The current feedback operational amplifier otherwise known as CfoA or CfA is a type of electronic amplifier whose inverting input is sensitive to current, rather than to voltage… …
69Charlieplexing — is a technique proposed in early 1995 by Charlie Allen at Maxim Integrated Products for driving a multiplexed display in which relatively few I/O pins on a microcontroller are used to drive an array of LEDs. The method utilizes the tri state… …
70Medical imaging — This article is about imaging techniques and modalities for the human body. For imaging of animals in research, see Preclinical imaging. Medical imaging Diagnostics A CT scan image showing a ruptured abdominal aortic aneurysm …
