A Schottky diode D connected to Vcc pin
2.A N-channel MOSFET connected to GND pin (see Figure 33: Typical application
circuit for DC to 10 kHz PWM operation short circuit protection
a P-channel MOSFET connesso al VCC pin
Inoltre, a series resistor must be inserted to limit the current sunk from the microcontroller I/Os. If IRmax is the maximum target reverse current through μC I/Os, the series resistor is:
R = (VIOs - VCC)/ (IRmax)
Somebody could please explain me how proceed?
I use Arduino uno through USB giving 3,3v to an IMU and 5v to the motor shield; with the two GND in common. For the motors I use a lypo battery 7,4v 2000mah.
Additionally, I'm not able to understand how to use enable pin, that have to be set HIGH. Can I put them on the 5v?
Admittedly the OP has not given a project objective or overview so we really don't know what he is building but the presence of motors suggests motion so I am going with :
raschemmel:
Admittedly the OP has not given a project objective or overview so we really don't know what he is building but the presence of motors suggests motion so I am going with :
I honestly don't believe you have any idea what they are talking about when they say "Short Circuit Protection" ( I believe they are referring to "Shoot-Through Prevention")
Do you know what "Shoot-Through" is ?
There are several ways to prevent it. One of them is tying the gates of the high side devices to the low side device on the same side. What does that accomplish ? If we ignore the "Master Enable" mosfet at the bottom (that has the diode backwards) , then the schamatic (diagram) you posted shows an H-bridge with 4 mosfets but two inputs (A & B), in addition to the ENA & ENB , plus a PWM input. By tying the HS gates to the LS gates , it is impossible for both the HS device and the LS device to be on at the same time because a TTL HIGH on either input turns OFF the HS device and turns ON the LS device, thereby preventing "Shoot=Through" (the short circuit they are referring to)
A Schottky diode D connected to Vcc pin
2.A N-channel MOSFET connected to GND pin (see Figure 33: Typical application
circuit for DC to 10 kHz PWM operation short circuit protection
a P-channel MOSFET connesso al VCC pin
Reverse battery protection is NOT short circuit protection - they are two different things.
The MOSFET at the bottom of that circuit allows current to flow providing the battery is connected the right way round because that way the FET is biased so that it turns on. If the battery is not connected the right way round then that FET will not switch on and so the bridge circuit will not be damaged.
The MOSFET at the bottom of that circuit allows current to flow providing the battery is connected the right way round because that way the FET is biased so that it turns on. If the battery is not connected the right way round then that FET will not switch on and so the bridge circuit will not be damaged.
That would be true if it was an N-channel mosfet but look at the source and the drain. If it was an N-channel the current flows from drain to source to ground , not the other way around. The above cstatement would be true for an N-channel at the bottom or a P-channel at the top. This is neither,and the diode is facing the wrong direction.
That's a P-channel mosfet with the arrow is going the wrong way on the gate,(for a P-channel it should go away from the gate. For an N-channel it should be going toward the gate). Either way it doesn't match the symbol for an N channel or P channel. Note the location of the source and drain.
If it's a P-channel it should be at the top between the upper Vcc and lower Vcc in the center. It is in the correct location
The OP's post is a request for Reverse battery protection methods.
1-As we all know, the best reverse battery protection, is PAY ATTENTION when connecting the battery !(duh)
2-The second most popular is polarized battery connector which PREVENTS connecting it backwards because it will only plug in one way. (all RC enthusiasts use this method for their Lipo batteries).
3-Then there is Schottky diode connected from Vcc to Ground with the cathode at the Vcc end.
4- A 1N4007 in series with the battery connector at the circuit end with the anode toward the battery connector and the cathode toward the circuit is pretty much fool proof but is unpopular due to the 0.7V drop across the diode. If the battery is feeding the ext. dc barreljack and is more than enough voltage then is a perfect solution.
