Constructing a MOSFET switch is one of the basic level electronics projects and could be useful for beginners to get a hang of the various FET transistors. Read through the article to know more on this.
The aim of this project is to make control a heavy DC load by constructing a simple switch. MOSFET transistors are capable of handling a large voltage and current. It is because of this feature that it is being much sought after for connecting heavy loads to a circuit or a microcontroller.
The MOSFET transistor can be triggered by a switch or an input pulse. A suitable input method can be selected by keeping a jumper on the correct side of the input header. THe pulse input would be the best option here. The switch input is better suited for a specific set of circuits. A 24V dc voltage is what is required here but other voltages can also be accomodated. Care has to be taken to ensure that the LED is provided with the right amount of current. The ability to power up an N-Channel power MOSFET is also required, but this should be done only if its pin matches that of the NTP6411.
The On Semiconductor NTP6411 power MOSFET acts as the central component of the circuit. The hectic task of turning a heavy load is performed by this transistor. It also ensures that absolutely no current is generated from the input signal. Input voltage is provided using a 12V generator, in case a switch control is used. In order to avoid inductive load voltage spikes, a flyback diode is introduced into the circuit. The transistor activity is deciphered visually by means of an LED. Multiple circuits can be joined together using dual power connectors. For heavy loads and long working periods, a heat sink might be necessary.
Load testing was performed on the circuit using an industrial air solenoid valve. The MOSFET worked without any problems but the valve turned hot. A small voltage causes a high on state resistance and hence care has to be taken while the using the circuit with a new application.
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