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Can a MOSFET be switched on with a BJT base?
For mosfets this is not true, in other words mosfets gate which is equivalent to BJT base, require minimal current to switch ON, regardless of the drain current (drain pin of mosfet is equivalent to collector pin of BJT). Having said this, although the current is not the deciding factor for switching a mosfet gate, voltage is.
How to drive a MOSFET from a low current PIN?
My intention is to drive a MOSFET (say, a IRF840 or some logic-level) from a low-current (<10mA) SoC output pin. Using appropriate resistors from gate to pin and ground, this works… but the gate voltage change could be faster. So I considered putting a NPN (to VCC) & PNP (to GND) BJT between the pin and FET
What is the switching voltage for a BJT?
But the switching voltage required at the base of a BJT can be as low as 0.6V or 0.7V. Meaning, BJT collector load could be switched ON with a voltage as low as 1V across base/emitter of a BJT.
Can a CMOS driver drive a FET gate?
You can buy a CMOS driver that drives a FET gate with several amps, for less than 1£$Euro. MOSFETS are voltage triggered and therefore they are perfect as they are with your microcontroler or SOC, as long as you use a pull-down resistor to pull the input to ground, you should be fine.
How are the base and emitter pins connected in a BJT?
BJTs have 3 leads or 3 pins, namely base, emitter, collector. The base pin is used for feeding the external input trigger, in the form of small voltage and current. The emitter pin is always connected to the ground or the negative supply line. The collector pin is connected to the load via the positive supply.
How to design Totem Pole BJT based MOSFET gate driver?
I need to design a totem bole bjt based gate driver for Mosfet IRF640, which is going to be used in a Buck converter. I know the peak gate charging current= 1A. I’ve already selected my complementary Bjt pairs ( 2N2222A, 2N2907A) so it can give a max current = 0.6A. The mosfet has a minimum V g s t h = 2V and max of 4V. Now how do I select Rg?
Why are two BJT transistors used in PWM mode?
In some books and articles they say that to protect the MOSFET from overheating when working in PWM mode two BJT transistors are used as in the image, others recommend the use of a driver for MOSFETs such as MCP 1404. What is the difference between using one or another?
Which is the best driver for MOSFET gate driving?
The driver is tailored for MOSFET/IGBT gate driving, it has also some protection like UVLO,..it may also ensure that gate is low (and not floating) in absence of Vcc. Thanks for contributing an answer to Electrical Engineering Stack Exchange!