MOSFET transistors are excellent choice for driving high current devices such as motors or high power RGB LEDs. They offer very low switching resistance and very small heat dissipation compared to bipolar transistors. This guide is designed to explain how to drive N-Channel MOSFETs with a microcontroller such as PIC or ATMEGA. Transistors heat up when driving large loads because they have a voltage dropped over them (Vce), and Heat (Watts) = Voltage * Current. This leads to thermal runaway within the transistor, eventually driving the device to destruction if not handled carefully. FET's are like digital switches, capable of turning on and off between the Drain and Source via a voltage potential at the Gate. When a FET is on, it usually has a resistance of less than 0.01 ohm, and when off, its like an open circuit. Because of the low resistance during the FET's on state, it can allow large amounts of current to pass through it without heating up. FET's turn on by voltage potential, not an electric current, and in return they have a very high input impedance. With this in mind, you only need a voltage to turn them on, perfect for digital electronics.

     AC Power Meter
     Wireless Security Alarm
     Using HSR312 / HSR412 Solid State Relays
     Animated Christmas Star
     Simple 300W Lamp Dimmer
     AC-AC Solid State Relay or SSR
     Sine Wave Synthesizer
     Plant Water Alarm
     Alarm Sounds When Refrigerator Door Remains Open Too Long
     Parrot Sounding AC door Bell

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