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What is the purpose of a MOSFET driver?
A MOSFET driver IC translates TTL or CMOS logical signals, to a higher voltage and higher current, with the goal of rapidly and completely switching the gate of a MOSFET. An output pin of a microcontroller is usually adequate to drive a small-signal logic level MOSFET.
What is a MOSFET driver IC?
A MOSFET driver is a type of power amplifier that accepts a low-power input from a controller IC and produces a high-current drive input for the gate of a high-power transistor such as an Insulated-Gate Bipolar Transistor (IGBT) or power MOSFET.
WHAT IS A gate driver IC?
A gate driver is a power amplifier that accepts a low power input from a controller IC and produces the appropriate high current gate drive for a power device. It is used when a PWM controller cannot provide the output current required to drive the gate capacitance of the associated power device.
Why do you need a MOSFET driver for a gate drive?
So, you also need the MOSFET driver to increase the drive voltage as well as the current. In the simulation examples given the gate drive used is 15V. For an example of a MOSFET driver, look at something like the Microchip TC1426. That is a dual MOSFET driver that will drive up to 1.2A and level shift up to 16V while interfacing to 5V logic.
What kind of capacitance does a MOSFET have?
Drive current – MOSFETs can have very high gate capacitance. For example, the IRF530NS from International Rectifier is a 90mW device which can withstand 17A continuous drain current at 100V and has 920pF of input capacitance.
How are high side NMOS used in MOSFET gates?
Using the capacitor shown between Vb and Vs (the source of the high side NMOS) and some circuity to the IC it creates a voltage higher than Vs by 10V to 20V and uses this to drive HO – the high side gate pin. This is in addition to providing level shifting from low level logic signals to drive the MOSFET gates.
Do You need A CPLD to drive a MOSFET?
If you want to drive a MOSFET from some logic such as a CPLD or microcontroller then you clearly need something to boost the current as your CPLD won’t drive 1A or even 100mA.