Error in pull up and pull down circuit

[aruwin]

Hello.
What would happen if there's a mistake in the pull up circuit where nMOSFET is used in the pull up circuit while the pMOSFET is used in the pull down circuit?
What would happen to the action of the inverter, output voltage range and characteristics?
I have been trying to find some clues in my textbook but I don't get it.

 

[jvicens]

Hello,

Thank you for your question. I can provide some insight into what would happen if there is a mistake in the pull up circuit where an nMOSFET is used instead of a pMOSFET.

Firstly, let's understand the function of an inverter. An inverter is a basic logic gate that has two inputs, a high input and a low input, and one output. The output of an inverter is the opposite of its input. For example, if the input is high, the output will be low and vice versa. This is achieved by using a pMOSFET in the pull up circuit and an nMOSFET in the pull down circuit.

Now, if there is a mistake and an nMOSFET is used in the pull up circuit, the inverter will not function as intended. This is because the nMOSFET is a type of transistor that allows current to flow when a high input is applied to its gate. This means that when the input to the inverter is high, the nMOSFET will turn on and allow current to flow from the supply voltage to ground, resulting in a low output. Similarly, when the input is low, the nMOSFET will turn off and no current will flow, resulting in a high output. This is the opposite of what an inverter is supposed to do.

Furthermore, this mistake will also affect the output voltage range and characteristics of the inverter. The output voltage range will be limited to the supply voltage, as the nMOSFET will always be in the on state, resulting in a low output voltage. The characteristics of the inverter, such as propagation delay and noise margin, will also be affected as the nMOSFET is not designed to be used in the pull up circuit of an inverter.

In conclusion, using an nMOSFET instead of a pMOSFET in the pull up circuit of an inverter will result in the inverter not functioning as intended, limited output voltage range, and altered characteristics. It is important to carefully design and implement circuits to avoid such mistakes. I hope this helps clarify your doubts. If you have any further questions, please do not hesitate to ask.