MOSFET Operation and Modeling

MOSFET Operation


Negative voltage applied to the gate attracts mobile holes to the surface under the gate.

Depletion (weak inversion, subthreshold)

Small positive voltage applied to the gate repels free holes, not negative enough to attract holes, not positive enough to attract many electrons.


Moderate positive voltage applied to the gate attracts free electrons from source and drain under the gate.

MOSFET Modeling

MOS Large Signal Model

In saturation, the drain current is basically

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Digital Electronics: Half-Subtractor, De Morgan’s Theorems, 2 to 4 Decoder, JK Flip-Flop, and Flip Flop Types

What is a Half-Subtractor?

half-subtractor is a combinational logic circuit that have two inputs and two outputs (i.e. difference and borrow). The half subtractor produces the difference between the two binary bits at the input and also produces a borrow output (if any). In the subtraction (A-B), A is called as Minuend bit and B is called as Subtrahend bit. The block diagram and logic circuit diagram of the half subtractor is shown in Figure-1.


What are De Morgan’s Theorems?

Two of the theorems

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Essential Git Commands Cheat Sheet

Essential Git Commands

Q1. Initializing a Repository and Adding a File

mkdir your_project_directory || cd your_project_directory || git init || touch your_new_file.txt || git add . || git commit -m "Initial commit - adding a new file"

Q2. Creating and Merging a Feature Branch

git branch feature-branch || git checkout -b feature-branch || git checkout master || git merge feature-branch || git add . || git commit -m "Merge feature-branch into master" || git branch -d feature-branch

Q3. Stashing Changes


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Understanding Shift Registers, Counters, and Logic Circuits

Explain the Operation of a 4-Bit Parallel-In, Parallel-Out Shift Register with Data Input 1010

A 4-bit parallel-in, parallel-out shift register is a digital circuit that can store and shift a 4-bit binary number. In this type of shift register, data can be loaded into the register in parallel (all at once), and the stored data can be read out in parallel as well.

Let’s explain the operation using the given data input of “1010”:

1. Parallel Data Input (1010)

Initially, let’s assume all the flip-flops

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Digital Logic Circuits: Half Subtractor, Decoder, Flip-Flops, and Shift Registers

Half Subtractor

A half subtractor is a digital logic circuit that performs the subtraction of two binary bits. It has two inputs, A and B, and two outputs, Difference (d) and Borrow (b). The output d is the difference between the two inputs, A and B, and output b represents a borrow, indicating that the subtraction of B from A requires borrowing from the next digit in a larger binary number.

A half subtractor can be used in combination with other half subtractors to build a full subtractor circuit,

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Understanding Microprocessors, Shift Registers, and DC Motors

Shift Registers Explained

a. SISO (Serial-In, Serial-Out)

In a SISO shift register, data is shifted in serially through one input (usually called the Serial Input) and is shifted out serially through one output (usually called the Serial Output).

  • Each clock pulse shifts the entire data content by one bit position.
  • It’s commonly used for applications such as data buffering and serial data manipulation.

b. SIPO (Serial-In, Parallel-Out)

SIPO shift registers accept data serially through one input and output

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