Contents
Can a MOSFET act as a flyback diode?
If you are using a full H-bridge (or half-bridge) the body diode of the other MOSFET (the one not switching) will act as a flyback diode, however the power loss may be more than through the MOSFET since the motor run current multiplied by Rds (on) can be less than a diode drop for a good MOSFET.
Which is the best MOSFET for high side switching?
Low-Voltage Complementary MOSPOWER Array. Properly driving the MOSFET gates can minimize unwanted crossover current at high supply voltages (both +V DD and ±V DD ) (Figure 6). A resistively-coupled lower-power complementary pair offers extremely low crossover current when the o utput stage uses high-power MOSFETs.
What makes a p channel MOSFET good for Fet?
To drive the FET properly, the gate voltage must be referencedto its source. For enhancement-mode MOSFETs, this gatepotential is of the same polarity as the MOSFET’s drainvoltage. To turn on, the n-channel MOSFET requires a positivegate-source voltage, whereas the p-channel MOSFETrequires a negative gate-source potential.
Which is the best diode type for flyback diodes?
Those are the preferred diode type for flyback diodes. I work as a technician for the railways and for our DC traction motors we use flyback diodes that could barely handle the forward motor current but their forward surge current is very high and those diodes rarely break. Thanks for contributing an answer to Electrical Engineering Stack Exchange!
What kind of diode do you need for a DC traction motor?
The type of diode you most probably need is a schottky diode. Those are the preferred diode type for flyback diodes. I work as a technician for the railways and for our DC traction motors we use flyback diodes that could barely handle the forward motor current but their forward surge current is very high and those diodes rarely break.
Why is the voltage so high in a flyback diode?
According to Faraday’s law of induction, if the current through an inductance changes, this inductance induces a voltage so the current will go on flowing as long as there is energy in the magnetic field. If the current can only flow through the air, the voltage is therefore so high that the air conducts.
Why is a Schottky diode added to a MOSFET?
Sometimes a Schottky diode is added (co-packaged) because the body diode is slow recovery. Since the Schottky diode has a lower Vf it conducts most of the current. It should be noted that the diode only comes into play in a configuration such as a half-bridge or H-bridge where the diode conducts when a different switch turns off.
Is the Zener diode the same as the flyback diode?
A zener diode in series but with reverse polarity with regard to the flyback diode has the same properties, albeit with a fixed reverse voltage increase. Both the transistor voltages and the resistor or zener diode power ratings should be checked in this case.