At Knowles Precision Devices, we have a long history in radio frequency (RF) and custom discrete passive components. Our rich heritage in variable and trimmer capacitors comes from Voltronics and Johanson and our expertise in High-Q multi-layer ceramic capacitors (MLCCs) is supported by DLI and Syfer. 

In other blogs, we’ve talked about inductors in terms of their role in lumped element filters. Here, we’re going to take a step back to discuss inductors and related passive electronic components, including air core inductors and baluns. 

In this new application note, we dive into the details on all things related to tuning elements. If you are unfamiliar with tuning elements, our line of Johanson Microwave Tuning Elements are specially designed for tuning microwave circuits such as filters, oscillators, delay lines, multiplexers, and dielectric resonant structures. Prior to the introduction of this line of Johanson Microwave Tuning Elements, microwave circuit designers were burdened with the frustrating task of selecting from a makeshift conglomeration of "hardware store" nuts and bolts to tune precision microwave circuitry.

In part 1 of this two-part guide, we talked about the trade-offs you need to make when selecting the type of capacitor that will be the best fit for your application and the basics of trimmer capacitor design including dielectric material options. This second post focuses more on the details of trimmer capacitor specs and how to determine what's right for your application.

As you already know, capacitors are essential circuit elements for storing and suppling charge on demand. For inductors and resistors, capacitors act as the building blocks of passive circuits and the supporting components for active circuits. While a wide range of fixed-value capacitors are used in most electrical circuits, it is sometimes preferable, or necessary, to use a component with a variable capacitance range.