Electronics FAQ – Your Multilingual Guide to Electronics

  How RC Low-Pass and High-Pass Filters Work — Simple Explanation with Examples Let me provide you with a basic understanding that will clear up any misunderstandings you may have regarding the capacitor in a high/low-pass filter. Mechanism of High/Low Pass Filter: ‘Filter’ word is a bit misleading. It doesn’t take ON/FF-type action. Filter only reduces (voltage) gain for a certain frequency compared to the whole spectrum of the frequencies of interest. A filter is basically a Voltage Divider:  The filter works on a voltage divider principle. Let me clarify. So, the output voltage reduces proportionally to the value of resistors R1 & R2. In simple words, the larger the R1 and the smaller the R2, Vout will reduce compared to Vin. Can I use the above circuit as a low-pass filter? No, because resistance doesn't change its value proportionally to the frequencies . So our goal of reducing gain for a certain band of frequencies wont be fulfilled. We need to replace R1 or R2 with...

How Does a Capacitor Reduce Ripple in DC? Working Principle, Smoothing Effect, and Applications. Why is it important in AC to DC conversion?  Filtwer capacitor analogy with a water tank: Suppose your home has intermittent water supply problems. When you need water, the supply is not sufficient. When you don’t need water, you don’t know what to do about the excess water. What is the solution to this problem? Have a water storage tank, don’t you? Similarly, unfiltered, raw rectified DC voltage is not as smooth as battery voltage. Unfiltered DC voltage:  As shown above, sometimes it is zero, sometimes it is maximum. It is always varying with respect to time. But electronic devices require a smooth DC voltage, as shown below. DC voltage of Battery:  The solution is to incorporate an electronic reservoir called a capacitor . AC to DC conversion using a diode and a capacitor:  Filtered DC voltage ripple waveform: It stores excess electricity and releases it to the load whe...

Why Are Capacitors Used in Speakers? Role in Audio speaker systems, Crossover Networks, Sound Quality Enhancement and distortion reduction.  A single speaker is unable to reproduce the entire audio range faithfully. Hence, not only capacitors, but also air-core inductors and resistors, are used to split the entire audio range into two or three components and assign them to the specific speaker that best represents it. Typical crossover circuit: A crossover circuit assembled PCB:  That said, designing a crossover is not a simple task. It needs extensive computer model simulation and several practical trials to match it to the speaker drivers, so that audio reproduction is seamless without any breaks. FAQ Set Q1: Why are capacitors used in speakers? Capacitors are used to   control the flow of high and low-frequency signals , directing them to the appropriate speaker drivers and improving overall sound quality. Q2: What is the role of capacitors in crossover networks? In cr...

How does a capacitor smoothens a voltage and how does an Inductor smoothen the current Take a large reservoir of water. Does the inlet of water increase the water level suddenly? No. Watertank analogy of a capacitor: Does the outlet of water suddenly decrease the water level? No. A capacitor is like a water tank. Inlet water is like a charging current. The outlet of water is like a discharge current. Water level is like the voltage of a capacitor. DC ripple filter: The process of how a capacitor maintains its voltage level is best explained by how a filter capacitor smoothens the DC ripple. When the incoming voltage increases, it charges to that voltage. When the incoming voltage decreases, it uses its stored energy to supply current to the load by maintaining the voltage level. As long as demand le less than supply, it comfortably maintains almost a constant level of voltage across the load. That is exactly what an overhead water tank in our home does when there is an irregular water ...