2WD Vehicle DIY H-Bridge and Power Source

Using Arduino General Electronics
1

I am just starting with my first project with Arduino. I am making a Bluetooth controlled 2WD vehicle. I am using the UNO, and need some help with the electronics.

First, I am using an H-Bridge made out of MOSFETs. Though I know using an IC like L293 would be a much better option, it is a sort of a requirement for this project that I make the H-Bridge myself. I have attached the schematic of the H-Bridge. I am using IRF9630 P Type and IRF630 N Type MOSFETs. There will be two of these for both the wheels. My question is that if this H-Bridge is safe to use with the Arduino UNO. From what I know, the UNO digital pins are rated at 40mA., and that MOSFETs have zero gate current, so it should be safe. I believe I don't need extra transistors for driving the high side because my H-Bridge voltage is 5v, which is the same as the logic voltage.

Secondly, if I am using a 7.4V battery pack to power the Arduino, can I use the same battery pack to power the H-Bridges, and use a 5V regulator like this one? I believe I cannot power the motors from the Arduino 5V output because the motors, 3-6 V, will exceed

Lastly, my HC-05 module came attached to a breakout board. Do I still need resistors to connect it?

I will be glad to have some help. Thanks for reading.

H-Bridge.png
H-Bridge.png850×459 13.5 KB

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That design will cause "shoot-through". A short period of time when switching where both top and bottom fets are on. Not a suitable design.

The mosfet gate acts like a capacitor it will use current charging/discharging the gate, you would still want to limit the current from the arduino pin by using a resistor in series with the gate.

There are many more suitable mosfet choices for low voltage applications than those mentioned. Also you would want logic level mosfets if you intend to drive them with 5 volts.

You can power the arduino with the 7.4v pack too as long as the motors don't cause too much voltage drop. If using a 7.4 volt motor source you need extra transistors to drive the top mosfets otherwise you would not be able to turn them off completely.