yes in find a LOGIC MOSFET IRLB8721 ALSO I CAN ADD AND OFFSET VOLTAGE (+5) AND THE PULSE IS BETWEEM 0 +10VAragon, in a previous post I said that the datasheet for the IRF520 says that with a Vgs of 4V it is at its maximum threshold voltage when it barely turns on only 0.25mA. It turns on fully when its Vgs is 10V that you do not have. I said to use an IRL520 that is fully turned on when its Vgs is 5V.
The IRF540 is exactly the same. You need an IRL540 instead that turns on fully when its Vgs is 5V. You need a Mosfet that is called "logic level".
Another problem with your -5V to +5V gate drive is that it takes a longer time to charge the gate-source capacitance from -5V to +5V than if the drive is 0V to +5V driving a logic level Mosfet.
I would use the IRL540 instead, it is logic level compatible. At Vgs of 4.0V, the RDSon is 0.11 ohms, and can handle over 20A at 100V. At Vgs 5.0V, RDSon is only 0.077 ohms.this is a good choice for low voltage
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and the IRLB8721PbF have Very Low RDS(on) at 4.5V VGSI would use the IRL540 instead, it is logic level compatible. At Vgs of 4.0V, the RDSon is 0.11 ohms, and can handle over 20A at 100V. At Vgs 5.0V, RDSon is only 0.077 ohms.
The key is to use a logic level MOSFET. Many of the IRF540 series (520, 530, etc) also have the IRL series of logic level MOSFETs. Only issue however, is that maximum Vgs is +/-10V, not 20V like most other IRF5xx series. You have to make sure your gate voltage does not approach 10V or more.
i run again the lab with IRLB8721PbF and a normal dc motor not (brusless)
according to data sheet the IRLB8721PbF is full open with voltage 4.5 V The rpm decrase with increase of frewuincy
This is a different motor? Or the same one? If it is the same one, how do you know it's not brushless? Just because it has only 2 wires to it doesn't mean it can't be brushless. Show a picture, a link or a part number of your motor.a normal dc motor not (brusless)
ΤΗΑΝΚ ΥΟU"The relation between the pwm frequncy and the rpm of a dc motor ?"
For brush DC motor the duty cycle related to the magnetic flux density.
https://www.researchgate.net/public...T_OF_PULSE_WIDTH_MODULATION_ON_DC_MOTOR_SPEED
by Aaron Carman
by Aaron Carman
by Aaron Carman
by Duane Benson