Weeds [MicroBusiness

Abstract

Discusses the concept of weeds and parasitic elements as they apply to the microwave engineering. Just as in gardening, there are weeds that one can keep in flowerbeds as well as those that are ripped out due to their hindrance to other grasses and flowers. Suggests that there are things like weeds in engineering too. Consider a transistor. Ideally, it is just a controlled current source. But real transistors have lots of parasitic elements—the weeds in a circuit. Sometimes we can take advantage of the parasitics in a circuit design. Consider, for example, the distributed amplifier. We use the parasitic gate and drain capacitances to realize artificial transmissions lines. These parasitics are, in essence, neutralized. Another place where we can make use of parasitics is in a microwave assembly. Examine other ways to make use of parasitics in microwave design and assembly.