Even with application circuits and reference designs available from many manufacturers, calculations remain a large part of a designer’s workload. Some may be simple, such as implementing Ohm’s law, while others are more complex, especially those relating to analogue design techniques such as filters, power systems and RF projects.

Mistakes can be made with even the simplest calculations, while complex mathematics can consume significant time. There is also the need to consider real-world effects such as parasitic elements that add more complexity, especially if high degrees of accuracy are required.

Fortunately, there is a wealth of resources online—many of which are free of charge—to assist designers. For example, Texas Instruments’ analog engineer’s calculator (Figure 1) is a Windows-compatible basic calculator that supports many common tasks, including using passive components, setting op-amp...