# EE4109 Structured electronic design

**Topics:**A systematic approach to the design of analog electronic circuits

The design of analog electronic circuits is considered by many people to be complex. This is mainly because designers have to deal with many relevant performance aspects that can be achieved in many different ways. In other words, there are many degrees of freedom for obtaining the desired performance of an electronic circuit. Theoretical concepts, circuit topologies, electronic devices, their operating conditions and the physical lay-out of a system, together constitute an enormous design space in which it is easy to get lost. For this reason, analog electronics is often regarded as an art rather than a solid discipline.

At first glance, there doesnâ€™t seem to be a straightforward way to design analog circuits and systems: experienced designers, intuitively, use all these degrees of freedom to modify and combine known solutions into new ones. However, intuition is knowledge the origin of which has become unclear. It cannot easily be shared with novices, and therefore, it cannot be a basis for the education of designers. The design of electronic circuits, however, can be shared and understood if it is presented in a structured way. This requires a clear formulation of design goals and strategies and a clear distinction between theoretical concepts and their physical implementations.

Instead of taking numerous existing solutions to known problems as a starting point, it is far more effective to start a new design with clear distinction between theoretical concepts and study how they can be implemented in such a way that the possibilities of the implementation technology are maximally exploited. Such an approach not only results in clear and reliable designs with predictable performance, but it also provides a basis for sharing and developing knowledge.

During the engineering phase, designers need to find or create real world components, determine their operating conditions and fix these conditions by design. To this end they need to formulate and solve so-called design equations for the circuit.

Design equations relate the properties and the operating conditions of the electronic devices to the performance requirements and the cost factors of the circuit. For example, in order to determine a budget for the gain-bandwidth product of an operational amplifier, we must find relations between this gain-bandwidth product and the performance requirements of the circuit that comprises this operational amplifier. I

Setting up design equations for analog circuits, especially at transistor level is a difficult and cumbersome task. It requires knowledge about technology, modeling techniques and interactions between the behavior of the circuit and the device properties. It goes hand in hand with symbolic analysis. Performing symbolic calculations by hand is sensitive to errors and in practice only a limited number of circuit performance aspects can be taken into account. For this reason, during this course we will use SLiCAP (Symbolic Linear Circuit Analysis Program). SLiCAP is written in MATLAB.

# Teachers

### dr.ir. Chris Verhoeven

Design methodology for Analog Electronics, electronics for nano satellites, electronics for (swarm) robots

Last modified: 2019-12-19