As we learned in our previous tutorial, passive filter circuits depend exclusively on passive components such as resistors (R) and capacitors (C) to provide filtering characteristics. A simple example is a first-order low pass filter built with a series resistor and a shunt capacitor across a sinusoidal input. Active filters on the other hand use […]
Understanding Passive Band Pass Filter with Formulas
The purpose of passive band pass filters is to filter or isolate particular frequencies within a given band. As a result, undesired frequencies outside of the intended range can be attenuated while the right frequencies can flow through selectively. As was previously noted, a non-polarized capacitor and a single series resistor may be used to accurately […]
Understanding Passive High Pass Filter with Formulas
As we already know, a low-pass filter selectively permits signals with frequencies lower than its cutoff frequency fc to pass through. This shows that although the high-frequency elements of the input signal are attenuated (weakened), the lower-frequency elements are retained in the output. A passive high-pass filter, on the other hand, functions in the opposite […]
Learning Passive Low Pass Filter Circuit Calculations
Basically passive RC filters are circuits that separate various frequencies within a signal. We can consider a signal as a collection of distinct-pitched noises. We can make an RC filter to only allow high-pitched sounds to pass through (such as a treble filter) or only the low-pitched sounds to pass through (similar to a bass […]
Understanding Capacitive Reactance with Formulas
Capacitors have a special way of opposing alternating current (AC) which is called capacitive reactance. This is like an internal resistance in the capacitor which changes based on the frequency of the electricity flowing through it. Unlike normal resistance which stays the same, no matter how fast the electricity changes (frequency), capacitive reactance is affected […]
Understanding Superposition Theorem, with Calculations
One method for analyzing electrical circuits is the Superposition Theorem. It is applicable to circuits that have several independent sources of voltage or current. The theorem basically enables us to dissect the functioning of the circuit and examine the role played by each source separately. In order to accomplish this, we temporarily disable all other […]