A voltage-controlled field-effect transistor with high input impedance.
A MOSFET controls drain current via gate voltage with an insulated gate, so it draws almost no DC gate current. N-channel and P-channel, enhancement and depletion types. Threshold V_th about 1–4 V for power devices. Dominates modern ICs and power switching.
A 30 V, 5 mΩ MOSFET can switch tens of amperes in a motor driver.
MOSFETs have very high input impedance and are the dominant transistor in modern chips and power electronics.
A voltage-controlled field-effect transistor with high input impedance.
MOSFETs have very high input impedance and are the dominant transistor in modern chips and power electronics.
A MOSFET is voltage controlled and draws almost no gate current, while a BJT is current controlled and needs a steady base current.
Low on-resistance gives small conduction losses, and the gate needs little drive power, which makes them efficient at high frequencies.
Typical applications include driving a high-current motor from a microcontroller pin, building a CMOS logic gate in a processor and switching power in a DC-DC converter with low loss.
Study "Common-emitter amplifier" first (topic 12 of 104 in Electronics & Embedded). It covers the groundwork this topic builds on.
High input impedance. Gate charge determines switching. Body diode.
A 30 V, 5 mΩ MOSFET can switch tens of amperes in a motor driver.
The next topic is "MOSFET regions of operation", which builds directly on this one.
It is classed as Beginner in Electronics & Embedded (topic 13 of 104). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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