The MOSFET is a three-terminal power switching component, in this article we try to discuss the MOSFET power supply. At the application circuits based on MOSFET, the power supply using MOSFET shows many advantages and disadvantages.
In this article, we explain some power supply circuits using MOSFET and also point out its pros and cons.
What is a MOSFET power supply?
We know MOSFET is one of the powerful semiconductor components, this is why they are been used in switching applications, high voltage, and high current applications.
The unique operation of MOSFET makes them have higher efficiency and higher switching capacity will makes them the best choice at power supply circuits.
The MOSFET is mostly used at power supplies for current booster purposes, the MOSFET can have the ability to deliver higher current.
PWM MOSFET power supply
The PWM or pulse width modulation is a method used to generate analog signal output from input digital signal.
The PWM MOSFET power supply setup is used to convert the pulsed signal from the PWM section into a voltage output.
Multiple conversion circuit sections are been used mostly on the switched-mode power supplies and at Arduino projects, so the power generation from the pulsed signal is the main purpose of the MOSFET power supply.
LM317 MOSFET power supply
The circuit shows the power supply using LM317 and MOSFET, the LM317 is the most popular voltage regulator IC which can have a voltage range of (0 to 24v) and a current limit of (1.5A).
The current boosting is the duty of the MOSFET in this circuit, the resistor adjusts to the MOSFET will provide gate voltage to trigger the MOSFET.
The BC547 transistor and resistor are for protecting the short circuit.
NOTE: The gate voltage need to trigger the MOSFET is 10v with a 1A current
LM723 MOSFET power supply
The figure shows the LM723 voltage regulator-based power supply, the purpose of the MOSFET is to provide a high current boost.
In this circuit R1 and R2 voltage divider network is used to provide adjustable function on the power supply circuit.
The MOSFET-based power supply circuit is normally based on a common drain configuration.
The MOSFET circuit threshold voltage is higher compare to other circuits and they behave differently at different current ranges, typical at higher current and the power consumption due to MOSFET is higher than other components.
And the MOSFET-based circuits are made to work with fast switching circuits, this is why at PWM power supplies MOSFET transistor is the perfect option.
But at the current booster power supply circuit, the BJT transistor is the best option than MOSFET.