Circuit technology

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The (electronic) circuit technology is an area of electrical engineering which, based on the theoretical methods of system theory, deals with the development, dimensioning and design of electronic circuits for specific purposes.

tasks and goals

An essential task of circuit technology is to provide systematic procedures and basic circuits for the design of electronic circuits for different areas of application. Such applications range from the amplification of small electrical currents and voltages to the implementation of complex circuits. In spite of the vast number of electronic circuits, only a few basic principles are applied:

Overall, circuit technology deals with all areas of signal processing , i.e. the generation, amplification, linking and conversion as well as the output of signals in the form of electrical currents and voltages. The area thus includes basic electronic circuits made of passive components such as resistors and capacitors , simple transistor circuits and complex microelectronic circuits and systems . Thus, the type of circuit technology also characterizes the type and design of the electronic circuit, but at the same time knowledge of the type of circuit technology does not allow any conclusions to be drawn about the function of the electronic circuit.

Classification

The circuit technology can be divided according to various criteria:

  • according to the type of processing signals
  • how the individual components are connected or mounted
  • according to the type of electronic components used
  • according to the type of interconnection of the components
  • according to the function of the circuit: For example the receiver or oscillator circuit technology. However, this classification is very imprecise and is not widely used in the literature.
  • according to application like high-voltage circuit technology in the field of electrical power engineering

Classification according to signal form

A basic classification criterion for sub-areas of circuit technology is the form of the electrical signals used by the circuit . A fundamental distinction is made between the processing of analog and digital signals and therefore between analog and digital circuit technology (also called analog and digital circuit technology ). In addition, there are circuits that use both signal forms or convert them into one another. Such circuits are the subject of mixed-signal circuit technology.

The subject of analog circuit technology is electronic circuits for processing signals that are continuous in value and time . Since no signal levels are used here and therefore no tolerance ranges exist, the temperature resistance of the component parameters is particularly important. In general, a much larger number of function modules and elements are used than in digital circuit technology.

The digital circuitry is concerned, however, with the processing of discrete-value signals , that is signals with graded values and provides the circuitry based on digital signal processing . Depending after the time at which occurs the signal quantization and So scan, one divides this area into two subgroups, the synchronous Circuit technology for periodic sampling times and asynchronous circuit technology for asynchronous sampling times, which are often determined by upstream assemblies.

Classification according to connection technology

The circuit technology can be divided into three categories with regard to the structure of the circuit: discrete, integrated and hybrid circuit technology.

The discrete circuit technology deals with electronic circuits in which all of the components in discrete form on a printed circuit board are applied, it is therefore also called printed circuit board technology. In the original form, only discrete basic forms of components, such as individual transistors or resistors , were used to build the circuit. For mounting the components on the circuit board typically come -through, (Engl. Through hole technology , THT) or surface mounting ( surface-mounted technology SMT) are used. The electrical lines between the components are implemented on the circuit board using photolithography and etching technology.

The hybrid technology is similar to the discrete circuitry, in contrast, however, both electrical wires and resistors are realized on the substrate at her. The so-called thick - film technology is used here. The other functional components, such as transistors or ICs, are applied to the substrate as discrete elements. Conventional assembly and connection techniques such as reflow soldering are used for this purpose.

In contrast, there is integrated circuit technology , it deals with electronic circuits in which all components (active and passive components as well as electrical lines) are implemented on a semiconductor substrate, i.e. the design of integrated circuits on transistor level. Integrated circuit technology is therefore a central component of microelectronics . Various semiconductor technology processes are used in production. From a circuit point of view, the spatial proximity of the individual elements plays an important role in integrated circuit technology. Because of this proximity, not only the electrical characteristics of the individual elements, but also their interaction and parasitic interactions, such as the latch-up effect, must be taken into account . Since not arbitrary, but often only a few, similar components are available, other circuit forms are generally used in integrated circuit technology. Active loads (load transistors) are used instead of electrical resistors and the individual circuit stages are coupled directly (see open collector output ).

Classification according to components and their interconnection

Another form of classification of circuit technology can be based on the components and interconnection techniques used. A fundamental distinction is made here between tube and semiconductor circuit technology . As the names indicate, either electron tubes or semiconductor components such as transistors and diodes are used to build a circuit.

Semiconductor circuit technology has been the most widely used circuit technology for several decades. In special cases, especially in digital technology, it can be divided into subgroups. In digital technology, some techniques are also / only known as "logic".

(List may be incomplete)

literature

Individual evidence

  1. ^ Karl Küpfmüller, Wolfgang Mathis, Albrecht Reibiger: Theoretical electrical engineering: An introduction . 18th edition. Springer, 2008, ISBN 978-3-540-78589-7 .
  2. ↑ a b Reinhold Paul: Circuit technology . In: Dieter Sautter, Hans Weinerth (Ed.): Lexicon Electronics And Microelectronics . Gabler Wissenschaftsverlage, 1993, ISBN 978-3-540-62131-7 , p. 922 .
  3. ↑ Johann Siegl: Circuit technology - analog and mixed analog / digital . 3. Edition. Springer, 2008, ISBN 978-3-540-68369-8 , pp. 2 .
  4. ^ Sebastian Dworatschek: Basics of data processing Walter de Gruyter , 1989, ISBN 3-11-012025-9 , p. 237 restricted preview
  5. ↑ Johann Siegl: Circuit technology - analog and mixed analog / digital . 2., arr. u. supplementary edition. Springer, Berlin / Heidelberg 2005, ISBN 3-540-24211-2 , pp. 20 .
  6. ↑ Kurt Hoffmann: System integration: From the transistor to the large-scale integrated circuit . Oldenbourg, 2006, ISBN 978-3-486-57894-2 , Chapter 10 BiCMOS circuits , p. 499 ff .