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Current sense amplifiers (also called current shunt amplifiers) are special-purpose amplifiers that output a voltage proportional to the current flowing in a power rail. They utilize a "current-sense resistor" to convert the load current in the power rail to a small voltage, which is then amplified by the current-sense amplifiers.
This amplifier is often referred to as a shunt-series feedback amplifier, and analyzed on the basis that resistor R 2 is in series with the output and samples output current, while R f is in shunt (parallel) with the input and subtracts from the input current. See the article on negative feedback amplifier and references by Meyer or Sedra. [8 ...
Blackman's theorem is a general procedure for calculating the change in an impedance due to feedback in a circuit. It was published by Ralph Beebe Blackman in 1943, [1] was connected to signal-flow analysis by John Choma, and was made popular in the extra element theorem by R. D. Middlebrook and the asymptotic gain model of Solomon Rosenstark.
The electrodes are connected to an amplifier, which measures membrane potential and feeds the signal into a feedback amplifier. This amplifier also gets an input from the signal generator that determines the command potential, and it subtracts the membrane potential from the command potential (V command – V m ), magnifies any difference, and ...
The common and simple approach to current sensing is the use of a shunt resistor. That the voltage drop across the shunt is proportional to its current flow, i.e. ohm's law, makes the low resistance current shunt a very popular choice for current measurement system with its low cost and high reliability.
Paul Voigt patented a negative feedback amplifier in January 1924, though his theory lacked detail. [4] Harold Stephen Black independently invented the negative-feedback amplifier while he was a passenger on the Lackawanna Ferry (from Hoboken Terminal to Manhattan) on his way to work at Bell Laboratories (located in Manhattan instead of New Jersey in 1927) on August 2, 1927 [5] (US Patent ...
The op-amp inverting amplifier is a typical circuit, with parallel negative feedback, based on the Miller theorem, where the op-amp differential input impedance is apparently decreased to zero Zeroed impedance uses an inverting (usually op-amp) amplifier with enormously high gain A v → ∞ {\displaystyle A_{v}\to \infty } .
That is, the feedback is then positive rather than negative. Frequency compensation is implemented to avoid this result. Another goal of frequency compensation is to control the step response of an amplifier circuit as shown in Figure 1. For example, if a step in voltage is input to a voltage amplifier, ideally a step in output voltage would occur.