What do you mean by amplifier block, Electrical Engineering

Q. What do you mean by Amplifier block?

An amplifier can be modeled as a two-port device, that is, a box with two pairs of terminals designated as input and output, as shown in Figure (a). The circuit model of the amplifier block shown in Figure (b) is developed on the basis of the following considerations:

1. Since, for most amplifiers, the input current is proportional to the input voltage, the input terminals in the model are connected by a resistance Ri, known as the input resistance of the amplifier.

2. Since an amplifier delivers electric power (to a speaker, for example), the output current can be represented by its Thévenin-source model. The Thévenin resistance Ro is known as the output resistance and the Thévenin voltage is a dependent voltage source Avin, where A is called the open-circuit voltage amplification.

Thus, the amplifier block is a linear circuit block in which the output is proportional to the input, and the amplifier is characterized by the three constants Ri,Ro, and A. The input and output resistancesmay be generalized to input and output impedances in ac systems. The advantage of the model is that all internal complexities are summarized in the three constants, thereby simplifying the analysis of electric systems with amplifiers. Power-supply connections are usually not shown in circuit diagrams since they would only clutter up the drawing. It is assumed, however, that there are always connections to some power source in order to bring in the power necessary to run the amplifier.

158_What do you mean by Amplifier block.png

Posted Date: 6/21/2013 12:47:01 AM | Location : United States







Related Discussions:- What do you mean by amplifier block, Assignment Help, Ask Question on What do you mean by amplifier block, Get Answer, Expert's Help, What do you mean by amplifier block Discussions

Write discussion on What do you mean by amplifier block
Your posts are moderated
Related Questions
Querying the GIS: Interfaces which use the querying facility are available with the RDBMS. In the network-mapping environment, these give accurate and reliable information to

i am battling with mesh, node anaalysis, superposition, node thevenin and norton equivalents

Define the term assembler directives. An assembler directive is a statement to provide direction to the assembler to perform the function of assembly process. The assembler di

schmitt triggering with emitter coupled transister

Explain Synchronous Generators? They can be utilized to produce or absorb reactive power. An over-excited machine produces reactive power when an under-excited machine absorbs

Explain SEGMENT assembler directive with example. SEGMENT: This directive described to the assembler the start of a segment along with name segment-name. The seg

what are the grond clearance for 220KV overhead transmission lines?

Q. A simple parallel resonant circuit with L = 50 µH is used to performthe frequency selection. The circuit is to be tuned to the first station at a frequency of 1000 kHz. In order

Achieving reforms goals using GIS applications: GIS could help in achieving the above reforms goals through various applications: •  Creation of consumer database and cons

Thyristor  Terminology The followings  terms are used in SCR  specifications: Latching current : The  latching  current is  the value of on stat e current  required  to mai