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In this technology the fixed function ICs such as, Multiplexers, demultiplexers, adders, comparators, code converters, shift registers and counters, etc. are used to design the digital systems. These SSI and MSI logic circuits include discrete logic gates, specific Boolean transfer functions and memory elements. The design flow of this technology is as shown in below figure. The system design specifications are listed first from the requirements of the system, from the design specifications, a truth table is generated. Each row of the truth table is converted in the form of Boolean expression using Boolean algebra or a Karnaugh map. This expression is then implemented on the digital trainer board using fixed function digital ICs.

Fig_Discrete Devices Technology

Advantages :

  1. The development cost is lower,
  2. Faster turn of the designs and
  3. Easy to test the circuits.

Disadvantages :

  1. The design requires Larger board space,
  2. The power requirements larger,
  3. The circuits can be copied by others.
  4. To modify the design additional features are required.