Ten Essential Skills for Electrical Engineers

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HOW TO DESIGN RESISTIVE CIRCUITS

Chances are good that every schematic diagram you’ve seen contained at least a few resistors. This component is an electrical workhorse, commonly used for establishing bias voltages, programming gain, summing signals, attenuating signals, and numerous other functions. Ideal resistors dutifully follow Ohm’s law, which has no frequency dependence, so it is easy to believe that designing with resistors is a simple task. This is probably the most common reason candidates are caught off guard and fail when asked to design simple resistive networks in interviews. This chapter will show you how to design and analyze practical resistive networks that solve problems you’ll encounter in interviews and in the workplace.

The resistor was probably the first component you studied in school. At that time, it was the only component in your toolset, so the problems you solved were limited to finding voltages and currents in DC networks. Doing these problems taught you valuable skills such as nodal and mesh analysis, but the problems were not particularly practical and perhaps not very interesting. As a graduating engineer your knowledge of circuit elements has broadened significantly and you have better computer tools to help with the mathematical manipulations. The examples and problems in this chapter should be much more interesting because they represent practical design problems; they should be more enjoyable because, after setting up the problems, we will ...