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I want to create a custom H-Bridge from discrete components. I have found out the design using MOSFETS alone. My goal is to be driven by Arduino pins (5V).

My questions are:

  1. Do I need a driver for the MOSFETS, or a can simply hook the Arduino outputs to the MOSFET gates? I have seen designs that two extra additional MOSFETS are added to be used as drivers. Some other designs use logic gates as drivers, such as the design linked here: https://www.petervis.com/dictionary-of-digital-terms/h-bridge-driver/h-bridge-driver-for-dc-motor-using-mosfets.html I am not sure I understand the purpose of the drivers. Is there a reason for not connecting the Arduino outputs to the transistor's base directly?
  2. In the above design linked above, the person has four diodes as well. Are they necessary?

This is a picture of the design on the above link, so you don't have to visit it:

enter image description here

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Do I need a driver for the MOSFETS, or a can simply hook the Arduino outputs to the MOSFET gates?

Yes, the logic devices are not usually sufficient. They need to be powered from 12 volts AND, you probably need anti-shoot-through protection AND, if the loads are heavy the driver needs to supply the gate capacitances with hundreds of mA for quick switching.

Is there a reason for not connecting the Arduino outputs to the transistor's base directly?

The logic drives need to be 12 volt compatible is the main reason.

MOSFETs use gate inputs. BJTs use base inputs

In the above design linked above, the person has four diodes as well. Are they necessary?

They are not usually necessary but, a bulk capacitor across the power rails close to the MOSFETs usually is when driving a motor.

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