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Mosfet Drain current Equations

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Knowing how to solve the MOSFET equation is an important thing in circuit design, as MOSFETs are used in most applications as a Switch. To mention the working of MOSFET in simple terms, we will control the flow of drain current by applying a voltage between the Gate and Source terminals. The calculation of drain current depends on which region the MOSFET is working in. Regions of MOSFET: There are three regions of operation for MOSFETs. Cut off region Linear or Ohmic or triode region Saturation region If the Gate-Source voltage(Vgs) is less than the gate threshold voltage(Vth), mosfet will not turn on, and we call it as Cut off region. If the Gate-Source voltage(Vgs) is more than the gate threshold voltage(Vth), and mosfet turns on, it can work either in the Linear or in the saturation region , depending on the applied Drain to Source Voltage(Vds). I have written the equation in the solution solver tool for solving the circuit. By using the above equations, we can solve the MOSFET circ...
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Inductor Selection Guide for buck convertor

 So I have gone through some resources and YouTube videos for selecting the inductor value and its core. I created a Google sheet with formulas and step-by-step calculations. Still going to a lot of resources for getting an overview and concepts in selecting an Inductor. Understanding and selecting the Inductor itself is a big deal in Electronics design. The simple loop of wire changes the whole game of electronics. Below is the link for the Google Sheet I have created for an Inductor selection. https://docs.google.com/spreadsheets/d/1sHzjs5yaAu-ykRy6xiypI9z0ANtOBfvS_CsEW4mq2XA/edit?usp=sharing
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Microcontroller Designing-Lets start with Basics...

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Don't know where to start or how to start, so let's start somewhere. I am writing this as a way of documenting what I know about microcontrollers.  My journey with microcontrollers starts with the Arduino board. I would say that I started practically without even knowing a little bit of theory about microcontrollers. It was back then, during my college days around 8 years ago, that I started my journey with Arduino as a way of learning about Internet of Things (IOT). I bought an Arduino and started programming from scratch--> blinking LED, printing on LCD display, playing with seven segment LED, getting sensor's data, activating relays, and more and more. Then I bought a NodeMCU wifi module. The real fun started there. Again, blinking LED, but this time through mobile and using the cloud. It's time to do Iron Man stuff, controlling loads through voice commands using Google IFTTT. Then build a mobile-controlled CAR. I even built an automated Car using Arduino. Maybe I...
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Online Board Charger (OBC) Topologies

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I have studied the Online Board Charger topologies being used in the chargers used for charging the electric vehicle. Just wanted to note down the key points that I came across. When we are talking about topologies used in the EV chargers, it's divided into two parts. The first section is the PFC (Power Factor Correction) Circuit, and the second section is the DC-DC Convertor topology. The PFC is further classified into single-phase and three-phase circuits. PFC Topology Single phase Classic boost topology Bridgeless boost topology Interleaved boost topology Totem pole Interleaved Totem pole Neutral point clamped (NPC) Three phase Two level PFC NPC 3 level PFC Vienna T-type DC-DC Convertor Topology LLC resonant convertor Phase shifted full bridge(PSFB) Single phase dual active bridge Dual active bridge in CLLC mode There was a time when I went through each and every Topology and kept everything at my fingertips. I have a good deck of PPT for reference, which has a lot of details ab...
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Three point theorem_Star-Delta conversion...Nightmare in circuit solving

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As mentioned in the title, this topic is a nightmare when doing circuit solving. I like to solve circuits a lot. I have done a lot of circuit solving. Everything will go so smoothly as we forget ourselves in the flow until the point we encounter something like below. The circuit is neither series nor parallel. Struck. That's it. Curious to find out the way to solve the circuit, after doing a lot of searches, I came across the long-forgotten theorem called Start-Delta and Delta-Star conversion. Yup, true I forget this theorem exist at all. I remember that I studied this in Circuit Theorem subject and also remember I have done lot of circuit solving that time. But when it needed, as usual it become long-forgetten. Coming back to topic, to make the circuit either in series combo or parellel combo, we use this theorem. The circuits conversion will look like below image. If we see closely, all three connections in the image are end up as same. Thus why it can be called to many names: St...
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Filter circuits working- Lets start with RC filter

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Now, it's time to explore the workings of the filter circuits. I have been thinking about where to start for too long. But we have to start it anyway; that's what matters. So the filter circuit is basically a voltage divider circuit. In case of resistance, based on the resistance value, the voltage gets divided, and we get the voltage across the resistance. In the above example, a 12V 10Hz AC signal drops to a 6V AC signal across the resistor R2, which obeys Ohm's law. Simple. In the case of a capacitor, the capacitive reactance depends on the frequency of the signals. Means that capacitive reactance increases with a decrease in frequency. The equation for the RC low-pass filter is given in the image below.  Let's try to calculate the output voltage. For the above circuit, we are getting an output voltage of around 6.22V across the capacitor for the 2 kHz signal. Let's try to simulate the same, and let's see the result. Let's play with different frequency va...
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Filter Circuits Intro

Understanding how filter circuits work is an important topic in electronics. It serves as a very important piece of the puzzle.  Wherever we go, whatever we do, everywhere we come across one thing for sure. Noise, noise, noise, noise, noise...  Yes, in real life, I have no idea of how to deal with this noise other than trying to ignore it. That also try only. But in electronics, that's not the case. We can eliminate the noise or control it however we want using this filter circuits. One thing I like very much in electronics is that we can control the outcome as much as possible based on whatever we want. Coming back to the topic. Filters play a major role in analog circuits, not only in that even in power circuits, we will use filter circuits to eliminate ripples. Its having a wide range of applications. Basically is we use it to eliminate the unwanted signal or amplitude in our desired signals. In one word, eliminate the NOISE. So, to understand the working of filters, one mu...
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