It is very common application to drive a relay with a MOSFET. From household applications to automotive are using this circuit. There are some aspects to consider like the stress on the MOSFET, the level of driving voltage to guarantee MOSFET saturation, the level of the actual voltage applied to the relay coil if enough to meet the requirement and
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You may not know how to use MOSFET as reverse battery protection. The most common method is using a diode. However, diode voltage drop is high and this will creat issue in low voltage circuits. That is the reason many use MOSFET as reverse battery protection due to its very low on state voltage drop.
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A linear voltage regulator is the easiest to deal with. It is very easy to create and do not need much technical knowledge to understand its behavior. It has two variations: series and shunt.
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Surge protection circuit is the one referred by many as protector for voltage spikes in AC grid lines; however it is not limited particularly in AC grid lines. Surge protector or surge protection device is a device that will provide surge suppression or voltage spike suppression so that sensitive devices will not get damage. Surge protector can handle voltage spikes
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Basic NPN Transistor Principles Universities are covering this topic very well but despite I still attempt to discuss NPN transistor principles that I think easier to understand for non technical people. NPN transistor is the name given to a bipolar junction transistor with two N type materials or negative carriers while there is only one P type material or positive
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Electrostatic discharge or simply ESD is a universal problem in electronic circuits. Capacitor as ESD protection is providing economical solution to the problem. I used to work in automotive electronics and we used high frequency capacitors to protect the exposed pins of our product. Exposed pins are the one accessible to users. There are several ways to protect devices from
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Transistor operation mode is can easily be determined by using mathematical equations. Don’t worry; these are not difficult equations. There are three operation modes to operate the transistor. These are cut-off, saturation and linear. In cut-off, the transistor is simply not conducting; so it is not a problem to send the transistor in this region. You can simply do that
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For power devices like power MOSFETs, power BJT and power diodes, heat sink is very important to provide thermal relief. From the name itself, it will sink the heat from the power devices and help controls the temperature in the safe zone. In this article I will discuss heat sink thermal resistance calculation. For a system with forced cooling method,
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The most common application of Optocoupler is signal isolation. It provides complete isolation because its input side is not electrically connected to the output side. Its input side is a light source which is commonly a LED, while the secondary side is a photo transistor. A photo transistor is also a transistor but without a base current. The absence of
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In optocoupler, CTR stands for current transfer ratio. This is comparable to the current gain beta in BJT. This is the most important parameters of an optocoupler to function normally. There are several factors that affect the CTR, read here. In this article we are going to focus what is the disadvantage of using Optocoupler with low CTR particularly in
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