2-Bit Full Adder using Logic Gates in Proteus
Hello Learners! I hope you are doing great. Welcome to The Engineering Projects. In our previous lecture, we discussed How to design Half Adder with Universal Gates. In today's tutorial, we are going to design Full Adder with Logical Gates.
In today's tutorial, we will learn the complete information about:
- What is Adder?
- What is Full Adder?
- How is the Truth Table of Full Adder?
- How can we design Full Adder in Proteus ISIS?
- What are the uses of Full Adder?
What is Adder?
Recalling from our previous lectures:
- The Adders are simple Logical Circuits that take the bits in as the input, sum the bits together and generate the sum and the carry at the output.
- Adders are present in computer architecture, mainly to control the addressing of the Arithmetic Logic Unit(ALU).
We classify the Adders into two types:
- Half Adder.
- Full Adder.
We have discussed half Adder in detail in our previous two lectures. Today we'll stress the Full Adder:
What is Full Adder?
There are two types of Full Adders:
We define the Full Adder as:
- A Full Adders is a simple Logical Circuit, that takes 3 inputs(1-bit each) and generates two outputs i.e. the Sum(1-bit) and the Carry(1-Bit).
- A Full Adder takes 2 inputs A and B, while the third input is actually the Carry Input.
- We have seen in the Half Adder that we took 2 inputs and calculated the Sum and the Carry but we have no way of adding that Carry back into the Sum.
- This problem is solved by the Full Adder, which takes the Carry and adds it in the Sum to get a final Sum.
- That's why, we can use multiple Full Adders in series to add any amount of Bits.
- For example, we can serially attach 8 Full Adders to add 8 Bits of data(1-byte).
The Full Adder plays an important role in computer hardware calculations i.e. ALU control, register addressing etc. Here's a simple 2-Bit Full Adder Circuit using Logic Gates:
Truth Table of 2-bit Full Adder
As discussed above, there are three inputs and two outputs present in Full Adder. Therefore, the Truth Table of Full Adder will have 5 columns in total:
The input combinations of the Truth Tables are followed through the formula:
Numbers of Combinations= 2^n
where
n is the number of inputs. In our case,
n=3
hence,
Numbers of Combinations=8
We start the truth table from zero bit. The right most input has the alternative inputs after each combination. The middle contains the alternative bits after two combinations. By the same token the left most changes the input bit after four combinations.
The Truth Table of Full Adder looks like this:
A |
B |
Cin |
Sum
|
C0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
0 |
1 |
1 |
0 |
0 |
1 |
0 |
1 |
0 |
1 |
0 |
1 |
1 |
1 |
0 |
0 |
1 |
1 |
1 |
1 |
1 |
1 |
Carry+A+B |
Sum |
Carry out |
Simulation of Full Adder in Proteus ISIS
To design a Full Adder in Proteus, get these components from the library:
Components Required
- XOR Gate
- AND Gate
- OR Gate
- Logic Toggle
- LED
- Ground Terminal
- Get the first five components from the Pick Library through the "P" button.
- As shown in the below figure, I have placed the 5 Logic Gates in our Proteus workspace.
- We have 2 XOR Gates at the top, after that we have 2 AND Gates and finally an OR Gate at the end.
- The circuit should look like this:
- Now, connect two Logic Toggles with the inputs of Logic Gate 1.
- Connect one Logic Toggle with the 2nd input of Logic Gate 3.
- Attach the LED with the Gate 3 output and ground the LED with Ground Terminal present in "Terminal Mode" on the leftmost bar of the screen.
- Repeat the above step for Logic Gate 5.
- Connect all the Logic Gates according to the diagram given next:
- Change the Input bits and record your own truth table.
- To understand the working better, we'll design a Truth Table that describes the output of each Logic Gate.
Input |
Output |
A |
B |
Cin |
Gate1
|
Gate2 |
Gate4 |
Gate3(Sum) |
Gate5 C0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
0 |
0 |
1 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
0 |
1 |
1 |
0 |
1 |
0 |
1 |
1 |
1 |
0 |
1 |
0 |
1 |
0 |
1 |
1 |
1 |
1 |
0 |
1 |
0 |
1 |
1 |
Carry+A+B |
|
|
|
Sum |
Carry out |
Truss, we got a Full Adder circuit through which we can make the calculations.
Uses of Full Adder
- Full adders are paramount for the on-chip Libraries.
- They are used in computers for table indices.
- They are used by the processor to add the addresses.
- Full adders are used in Arithmetic Logic Unit.
- Full Adders are used in the Computer for the series calculations. For this purpose, they may be connected in the way given next in the image. Observe it from bottom to top.[TEPImg6]
- It can be designed so, that we can input eight bits together that collectively work as a byte.
So, that was all for today. We discussed What are Adders? What are Full Adders? Truth Table of Full Adder and how can we design Full adder in the Proteus software.
I hope this article was useful. In our next lecture, we will discuss
4-Bit Full Adders in detail. Thanks for reading.
What are DLD Logic Gates? Symbol | Truth Table | Simulation
Hello Mentees! I hope you all are doing well. In today's article, we'll learn about the very basic pillar of Digital Logic Circuits i.e. Logic Gates. As we know, the digital world depends on Boolean digits either 0 or 1. So, there's always a need to perform different operations on these boolean numbers i.e. addition, subtraction, multiplication, shifting etc. In order to perform these operations on the binary signals, we use Digital Logic Gates in DLD circuits.
So, let's have a look at What is a Logic Gate:
What is a Logic Gate?
- Logic Gates are designed to perform a specified operation(i.e. addition, bit shift etc.) on the input signals and generate the output signal.
- For example, a simple NOT gate takes a single binary input and returns its inverse in the output, i.e.
- If Input is 0, the Output will be 1.
- If Input is 1, the Output will be 0.
- We can design Logic gates using basic electronic components i.e. resistor, diode, transistor, etc. However, in order to design gates for commercial use, two main manufacturing technologies are used, i.e:
- TTL(Transistor-Transistor Logic): TTL Logic gates use NPN & PNP Bipolar Junction Transistors in their circuitry i.e. 7400 series.
- CMOS(Complementary Metal Oxide Silicon): CMOS Logic Gates use MOSFET or JFET transistors(i.e. 4000 series)yea ri and are quite popular because of their ultra-quick response.
Symbolic Representation
- Each Logic gate is assigned a symbol for its representation, which simplifies the designing of their circuit diagrams.
- The symbolic representation of 4 basic logic gates is as follows:
Truth Table
- Every logic gate has a truth table(also called a logical table), used to provide the output states for all the possible combinations/conditions of its inputs.
- It's a convention to write the outputs in the right-side columns and the inputs in the left-side columns.
- The truth table of NOT Gate(used to inverse input), is shown in the below figure:
- As you can see in the above figure, the table has 2 rows in total giving us all the possible input conditions.
- The number of rows in a truth table depends on the number of inputs used. The formula is, if we have "n" number of inputs in a logic gate, its truth table will have 2n rows in total. So, if we have 2 inputs, the rows of its truth table will be 22 = 4.
Truth tables are useful in Boolean and mathematical
operations as the relationship between the Input and Output can be
understood at a glance.
Now let's have a look at the Circuit Designing of Logic Gates:
Logic Gates Circuit Designing
As we discussed earlier, different Manufacturing Techniques are used to design logic gates. These techniques decide the characteristics of the logic gates i.e.
response time, noise immunity, voltage level for logic shifting etc. We can use simple electronic components i.e. diode, transistor, resistor etc. to design logic gates. The normal practices for designing logic gates with simple electronic components are:
- RTL (Resistor-Transistor Logic)
- DTL ( Diode-Transistor Logic)
- ECL (Emitter-Coupled Logic)
- DRL (Diode-Resistor Logic)
Such logic gates are quite simple in designing and normally have quite low response time and may also provide false output because of noise. So, in order to overcome these issues, these two manufacturing techniques are used:
- TTL(Transistor-Transistor logic)
- CMOS(Complimentary Metal oxide Semiconductors)
Simple NPN and PNP transistors are used in TTL logic gates and thus have better response time as compared to basic logic gates. In the CMOS technique, MOSFET and FET are used to control the logic and thus provide the best response time and are quite immune to noise. So, among all these manufacturing techniques, CMOS is considered the most popular technique for logic gate designing.
Logic Gates Designing with Basic Components
Here is an example of an AND Gate design with a Diode-Resistor Logic(DRL) and a NAND gate designed with Diode-Transistor Logic (DTL):
As you can see in the above figure, these circuits are quite easy to design, as simply using diodes, resistors, and transistors. But these circuits are not used in commercial ICs because of their high power loss(pull-up resistor) and gate delay(propagation delay). That's why, CMOS and TTL are considered the better option to design digital logic gates.
TTL Logic Gates
In TTL Logic Gates, NPN and PNP transistors are used for designing logic gates. The ideal TTL logic gate is the one that gives the LOW(0) Logic at 0V and HIGH(1) Logic at 5V. In a real TTL Logic Gate, the logic will be considered LOW(0), if the voltage level lies between 0-0.8V and the logic will be considered HIGH(1), if the voltage level is in the range of 2-5V. The voltage level between 0.8-2V is considered a "no man's land" and normally external pull-up or pull-down resistors are used to avoid this region. Examples of TTL Logic Gates ICs are 74Lxx, 74LSxx, 74ALSxx, 74HCxx, 74HCTxx, 74ACTxx etc. The switching voltage varies from group to group according to their internal structure and material used.
CMOS Logic Gates
In CMOS Logic Gates, FET(Field Effect Transistor) and MOSFET are used to design the logic gates. CMOS logic gates provide a LOW(0) logic, if its voltage is in the range of 0-1.5V and it will give HIGH(1) logic, if it's in the range of 3-18V. The below table shows the voltage levels of both TTL and CMOS logic Gates:
Logic Gates
|
LOW(0)
|
HIGH(1)
|
TTL
|
0-0.8V
|
2-5V
|
CMOS
|
0-1.5V
|
3-18V
|
Now, let's have a look at the Types of Logic Gates:
Types of Logic Gates
- There are numerous types of Logic gates available based on the
quantity of input/output channels and the type of logic to be applied.
- Based on the specified logic, gates are divided into 3 basic types, i.e.
- AND Gate.
- OR Gate.
- NOT Gate.
- These 3 basic gates are the building blocks of all advanced logic gates. So, we can design any advance logic gate with
these 3 basic logic gates.
- The most commonly used Advance Logic Gates are:
- NAND Gate.
- NOR Gate.
- XOR Gate.
- XNOR Gate.
- The above-mentioned 7 logic gates are the most commonly used ones. Following logic gates are not that common but are in practice:
- MIN(Minimum) Logic Gate.
- MAX(Maximum) Logic Gate.
- INH(Inhibit) Logic Gate.
- MAJ(Majority) Logic Gate.
- IMP(IMPLY) Logic Gate.
It's quite difficult to cover all these gates in a single lecture. So, we will only discuss the basic 7 gates i.e. AND, OR, NOT, NAND, NOR, XOR and XNOR. Today, we will have a brief overview of these 7 logic gates but in the upcoming lectures, we will cover each one of these individually in full detail. Here are the symbols of few logic gates:
So, let's get started:
AND Logic Gate
- AND Gate is a basic logic gate and gives HIGH output, when all of its Inputs are HIGH and generates LOW output, if any of its Inputs got LOW.
- The AND Gate performs the Logical conjunction. We denote it with the DOT between the inputs i.e. A.B = Y where A & B are the inputs and Z is the output.
- The Inputs in AND Gate is always more than one i.e. Inputs >= 2 and it will always generate a single output.
- The logical symbol of the AND gate is shown in the below figure:
Truth Table:
- Here's the truth table of AND gate in tabular form:
A |
B |
A.B |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
1 |
As you can see in the truth table of AND Gate, the Output is 1 only when both of its inputs are 1, otherwise, it's 0.
Proteus Simulation of AND Gate
Proteus has an AND Gate component in its components library. We are going to use it to verify the truth table of AND Gate. We will use the following components for designing this AND Gate Simulation:
- AND Gate
- LED
- Logic Toggle
- Ground Terminal
Here's the Proteus simulation of all possible states of the AND Gate with 2-inputs:
- I have placed a Logic State at the inputs of the AND gate and an LED at the output.
- The LED glows only when both of its Inputs are 1(HIGH).
OR Gate
- OR gate performs the Disjunction Logic on the inputs i.e. The output will be 1(HIGH), if any of its Inputs is 1(HIGH) and the output will be 0(LOW), if all of its Inputs are 0(LOW).
- OR Gate is denoted by a plus sign "+" between the inputs i.e. A+B = Y, where A & B are the inputs and Y is the output.
- Identical to AND Gate, OR Gate also has a minimum of two inputs and only one output.
- The OR Gate Symbol is shown in the below figure:
Truth Table:
- Here's the truth table for the OR Gate:
A |
B |
A+B |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
0 |
1 |
1 |
1 |
1 |
In the case of OR Gate, the output is LOW, only when all of its inputs are LOW, otherwise its HIGH.
Proteus Simulation of OR Gate
- The simulation is quite the same as that of the AND gate, we simply replace the AND Gate with OR Gate, present in the Proteus components library.
- The below figure shows that the output LED is OFF, only when both inputs of OR gate are LOW.
NOT Gate
- In Logic Circuits, the NOT Gate performs the inversion.
- This is a unary logic Gate that implies it has only one input and a single output.
- The output of NOT Gate is denoted by a Bar or Complement on the input symbol i.e. If the input is A, the output will be A'.
-
Here's the symbolic representation of NOT Gate:
Truth Table:
- Here's the truth table of NOT gate, quite simple isn't it?
Proteus Simulation of NOT Gate
- Grab the NOT Gate from the Proteus components library.
- Attach LED and logic toggle at output and input respectively.
- Here are the results:
So, today we discussed the basic logic gates i.e. AND, OR and NOT Gate and simulated them in Proteus. In upcoming lectures, we'll use these gates to design advance gates and circuits. Take care!!!
JFET Applications | Constant Current Source | Chopper
Hi Pupils, Welcome to another Experiment of Proteus at The Engineering Projects. Previously, we saw what are the Junction Field Effect Transistors. Today we'll learn about some of the applications of Junction Field Effect Transistors.
Just before the Experiment, it is useful to revise that:
Transistors are three terminal, unipolar Devices. The terminals of Junction Field Effect Transistor are named as :
The Gate Terminal is common to both Source and Drain.
Prior to start, let's clear some Concepts about Junction Field Effect Transistor.
Resistor
Resistor is an electrical device. we define the resistors as:
"A Resister is a two terminal Passive electrical device that shows the electrical resistance and is useful in almost every Circuit.
Resistors can be used to reduce or control the flow of current , terminate transition lines and such other functions.
Pinch off voltage
The basic Definition of Pinch off voltage is:
"The voltage applied between the Drain and the source at which the current maximum current flows through the circuit provided the Gate voltage is zero is called the Pinch off voltage."
when the value of voltages is less than the pinch off region, the voltage enters to another region called ohmic region of JFET and the transistor acts as a resistor in this region.
Controlling Voltage
The Controlling Voltage of Junction field effect transistor is defined as:
"The controlling Voltage is the voltage of transistors from gate to source. To set its value, the Voltage from gate to source is made negative and it is referred as Vgs."
FET's are widely used in the worlds of electronics because of their size and the performance. We'll apply JFET's in the making of two of circuits:
- Constant Current Source.
- Chopper.
During the Implementation of the Circuits, we'll use N-type JFET because of the better flow of electron of this kind of JFET. In N-type JFET the majority charge carriers are electrons.
I am going to explain it one after the other.
Constant Current Source
A Field Effect Transistor can be use as a constant current Source. That spell out that if JFET's are designed so, they can provide a constant current across the load resistor, no matter how much current is provided at its input. The ability is due to the near horizontal line in the drain characteristics of the JFET.
Recall that resistor is a two terminal Device that reduces the current flow, divide voltage or adjust signal lines. But, carefully Controlled JFET can be used to overcome the resistance through the resistor that come in between the JFET and the Voltage source.
In the circuit, when the Vgs is greater than the pinch off voltage. mathematically,
V-IR>|V|
Implementation in Proteus ISIS
To make the circuit for Constant current Source, we need the Components as:
Component Required:
- Junction Field Effect Transistor
- Resistor
- Ground Terminal
- Direct Current Power Supply
- Connecting Wires
Procedure
- Fire up your Proteus Software.
- Choose the JFET and Resistor from the Pick library through the "P" button.
- Take the Ground Terminal from Terminals library from the left most tab.
- Take DC power source from the "Generator mode".
- To measure the Current we'll add a DC ammeter from the "Virtual Instrument Mode".
This is the step where the Circuit should be arranged so, to get the required output.
- Connect the Source with the Drain thorough a wire.
- Join the Ground Terminal with the wire that connects Source and Gate.
- Connect the Components on the Working area according to the diagram:
- Double Click the Battery and give it a value of 9 volts.
- Double click the voltmeter and change the display Range to milliamps.
- By the same token, Double tap the resistor and give it the value of 1k ohm.
NOTE: you can also use a variable resistor.
- Record the values of the ammeter.
- At first observations, Change the value of resistor to 1kohm.
- Pop the play button.
The ammeter shows the value of the
0.40 miliamps.
- Take seven reading by changing the value of resistor and make a table.
Resistance |
Current |
1k ohm |
0.40 *10-3 |
2k ohm |
0.40 *10-3 |
3k ohm |
0.40 *10-3 |
4k ohm |
0.40 *10-3 |
5k ohm |
0.40 *10-3 |
6k ohm |
0.40 *10-3 |
7k ohm |
0.40 *10-3 |
The same experiment can be done by varying the value of battery and recording the values.
Chopper
A Chopper is the application of Transistor that show us the output as the square wave. We define the Chopper as:
"Chopper is an electronic circuit used to take the amplified Direct current by using some type of transistor or other device."
One can use any kind of transistor e.g Bipolar Junction Transistor tor make the Chopper circuit. But, Junction Field Effect Transistors are better for this purpose due to the field control of the JFETs.
In Choppers, the FET act as a variable resistance.
Lets rush towards Proteus to apply the circuit.
Implementation of Choppers in Proteus ISIS
- Fire up your Proteus ISIS.
Material Required
- Junction Field Effect Transistor
- Resistor
- Alternating current source
- Ground
- Oscilloscope
- Pick the Vsine , Resistor and JFET from the Pick library by the mean of "P" button.
- Take the Oscilloscope form "Virtual Instrument Mode" and fix it just above the Circuit.
- Connect Channel A just after the AC source and channel B with the Source.
- Put the Ground terminal below the circuit by choosing it from "Terminal".
- Change the value of resistance connected to AC as 100ohm.
- Change the value of resistance connected to Source as 200ohm.
- Give the frequency to 1000Hz and Amplitude of 12V to Vsine.
- Join the circuit according to the image given below:
Seems like our circuit is complete now.
- Press the Play button to simulate the graph.
- Set the Value of Channel A to 1V.
- Set the channel B to 20V.
The Output of the circuit is:
This Conversion is important in some Circuits. The output of the Chopper is in the form of square waves.
Thus, today we learnt about the JFET along with the applications of JFET as Constant current and Chopper in detail and saw their Implementation in the Proteus.
What are Digital Latches? | SR-Latches | D-Latches
Hi mentees, we are here with a new tutorial. I hope you all are fine. So far, we have been designing combinational circuits i.e. Adder, Subtractor, Multiplexer etc. using logic gates. But from today onward, we will design sequential circuits using logic gates i.e. Latches, Flip Flops etc. Let's quickly recall what's the difference between combinational & Sequential Circuits:
Combinational Circuits:
- Combinational circuits only use the current state of the input values to generate the output.
- Examples of DLD Combinational Circuits are: Adders, Subtractors, Multiplexers etc.
Sequential Circuits
- Sequential Circuits use both the current & previous states of the inputs to generate the output.
- Examples of DLD Sequential Circuits are: Latches, Flip Flops, Timers, Counters etc.
Digital Memory Elements
Normally two types of memory elements are used in digital circuits to store binary data, named:
- Latches
- Flip Flops(We will cover in the next lecture)
As today's lecture is on Latches, so let's explore it:
What are Latches?
- Latches are used in digital circuits as a memory element and are used to store/save the input states.
The two inputs of Latches are called "S" and "R" where S stands for SET and R stands for RESET. Due to inputs , latches can have four unique combinations of the input. The output is denoted as "Q" and is totally dependent on the input Combination.
Nevertheless, another Output is also used in the circuit sometimes. this output is denoted as Q' and is read as Q bar, Complement of Q or bar Q NOT Q because it is also written as:
One can have an idea that this output is the invert result of "Q" output and depends on the Q and successively to the inputs S and R.
Two types of circuits are possible in latches:
- Active high circuits.
- Active low circuits.
Both of them are same in the Components but are different due to the arrangement of the Components.
Active high circuits: In this kind of the Circuit the inputs are grounded and therefore are LOW. Latch are triggered momentary high signal.
Active Low Circuits: In this kind the inputs are LOW and the latches are triggered at high signals.
TYPES OF LATCHES
Latches are classified into two main types:
- SR Latches
- D Latches.
whereas, 1st two types are further subdivided into two categories:
- Simple
- Gated
All of theses types along with the implementations are shown in figure on right side.
Prior to start DO YOU KNOW???????
- Logic Probes are used to give input to the circuit. They can only give two types of inputs:
- High ( Denoted by 1)
- Low ( Denoted by 0)
- By the same token, Logic toggle show the output. There are two types of output:
- High ( Denoted by 1)
- Low ( Denoted by 0)
- NAND gate shows the output LOW ( or 0) only when both the inputs are HIGH.
- NOT gate show is an inverter gate.
- NOR gate shows the output HIGH ( or 1) only when both the inputs are HIGH.
Implementation of Latches in Proteus ISIS
For best understanding, we'll design each of the type and create the truth table.
Devices Required:
- AND Gate
- NOT Gate
- Three input AND Gate
- Logic Toggle
- Logic Probe
- Clock
Procedure:
All the Circuits follow almost same procedure. Even so, they are different in the Construction and the characteristics.
1. SR Latches in Proteus ISIS
- Choose Two NOR Gates and fix them on the working area.
- Examine the Circuit diagram and arrange the other required Components according to the Circuit diagram.
- Truss all the Components by wires with the help of circuit diagram.
- Pop the Play button and fill the truth table.
NOTE: You can also make this Circuit with NAND Gate.
Examination:
The SR latch ( SET/RESET) mainly change according to the change in the S line. that means, whenever the S is HIGH the Q ( output) is shown as HIGH and vise versa. but when both the inputs (SET & RESET) are HIGH then we seen that both the outputs are LOW. Q ( output ) is alway the inverse of Q'.
Once we check all the Conditions we can assemble our own truth table. I have made a truth table that shows us the following result:
S |
R |
Q |
Q’ |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
1 |
1 |
0 |
0 |
1 |
1 |
1 |
0 |
1 |
2. Gated SR Latch in Proteus ISIS
The SR latch are not Complete, hence the performance can be enhanced by the a process called "Gating" , and the resultant circuit is called Gated SR Circuit.
- We add two Positive NOR gates at the input "S" and "R" that have inverted input using NOT Gates. In this way we can examine the Condition more clearly when both the inputs in SR gate were HIGH.
- The circuit works well when we add a clock in the two inputs of the NOR gates.
The Circuit of Gated SR is shown next:
When we test the Circuit's all conditions , the output have some difference. The output here shows us the difference. During the LOW conditions of the Circuit the output shows us the error or Latch.
CLK |
S |
R |
Q |
Q’ |
0 |
X |
X |
LATCH |
LATCH |
1 |
0 |
0 |
LATCH |
LATCH |
1 |
0 |
1 |
0 |
1 |
1 |
1 |
0 |
1 |
0 |
1 |
1 |
1 |
1 |
0 |
3. D Latches in Proteus ISIS
D latch is a modification of the Gated SK Latch.
- we add the NOT Gate in advance of the RESET (R) Input and we get the circuit that looks like this:
Accordingly to the Picture, the D and clock are now the inputs of the Circuit and we can notice the output at Q and Q'.
CLK |
D |
Q |
Q’ |
0 |
0 |
NO CHANGE |
NO CHANGE |
0 |
1 |
NO CHANGE |
NO CHANGE |
1 |
0 |
0 |
1 |
1 |
1 |
1 |
0 |
4. Gated D Latch in Proteus ISIS
This is another type of D Latch.
- Connect the clock with the D input so that we alter the D input. But with this change, we see the changes in the output as well.
Let's have a look on the Circuit of Gated D Latch:
when we change the D and test all the Condition, the resultant truth table is:
CLK |
D |
Q |
Q’ |
0 |
0 |
0 |
1 |
0 |
1 |
1 |
0 |
1 |
0 |
1 |
0 |
1 |
1 |
0 |
1 |
Hence today we learnt about the latches, some basic concepts and its types along with practical implementation.
Shunt Clippers and Dual Clippers in Proteus ISIS
Bonjour trainees!!! Welcome to the Engineering projects, We hope you are doing great. In our previous lecture, we discussed the first type of clippers in detail i.e. Series Clippers. Today, we are going to discuss the next two types of Clippers i.e. Shunt Clippers and Dual Clippers. Here are the types of Clippers from the last lecture:
So, today, we are going to cover the below concepts:
- what is a Shunt Clipper?
- Types of Shunt Clippers
- Implementation of shunt Clippers in Proteus ISIS.
- Dual Clippers basics.
- Implementation of Dual Clippers in Proteus ISIS.
So, let's get started:
What is a Shunt Clipper?
- In Shunt Clippers(Parallel Clippers), the diode is connected in Shunt(Parallel) to the input signal source & the load resistance, as shown in the below figure:
As the diode is in parallel with the load & source, so during the positive half cycle, the diode will be in the forward-biased state(short circuit) and thus no current will flow to the load
resistance. While during the negative half cycle, the diode will be in a reverse-biased state(open circuit) and the load resistance will get all the current flow.
Now, let's have a look at the types of Shunt Clipper:
Types of Shunt Clippers
Shunt clippers are Classified into four main types, named:
- Positive
- Positive with bias
- Negative
- Negative with bias
Let's implement these Clipper types in the Proteus:
Implementation of Shunt Clippers in Proteus
So, open your Proteus software and add these components:
Components Required
- Vsine
- Diode
- Resistor
- Ground terminal
- Oscilloscope
- We can get the first three components from the "Pick library" by searching for the required component.
- We can get the Ground Terminal by left-clicking on the screen and then go to Place>Terminal>Ground.
- Get the Oscilloscope from the "Virtual Instrument" in the leftmost bar.
Now let's design the first type of Shunt Clipper:
Positive Shunt Clipper:
Now place the above components in the Proteus workspace and design the circuit, as shown in the below figure:
As you can see in the above figure, the diode is placed parallel to the load resistance. The arrowhead of the diode points opposite to the input source. As we discussed above, the load resistance will get voltage only if the diode is in a reverse-biased state. In the current arrangement, during the negative cycle of the AC signal, the diode will be reverse-biased, and the load will get complete power. The positive cycle of the input will be clipped off, as the diode will be in a forward-biased state, not allowing any current to flow through the load.
Change the values of components according to the below table:
Components |
Value |
Resistor R1 |
600 ohm |
Resistor R2 |
500 ohm |
Vsine |
Amplitude =110V,Frequency= 1000Hz |
Oscilloscope |
Time= 0.2m-1,Voltage 20V |
- Now run the simulation and you will definitely acquire the required output:
Positive with bias:
If you recall from our previous lecture on Series Clippers, we have added a battery in the bias clippers. Here, we are going to do the same, as shown in the below figure:
As we can see in the above figure, a battery of 5V is added in series with the diode. By adding the battery in the circuit of positive shunt clippers, we can easily control the amount of signal to be clipped. This arrangement is called Positive Shunt Clippers with bias or Biased Positive Shunt Clippers.
In the above circuit, we placed the battery just after the diode and the
Positive Terminal of the battery connects with the diode's arrowhead and
the negative terminal is connected to the Vsine source.
Here's the output of Positive Bias Shunt Clipper:
Negative Shunt Clippers:
In negative Shunt Clippers, the diode polarity is reversed i.e.the positive end of the diode is connected to the negative terminal of the battery and the negative end of the diode is connected to the positive terminal of the battery, as shown in the below figure:
In this arrangement, the diode is forward-biased during the negative half cycle, so no current will pass to the load. We can say, the negative cycle is clipped off. While in the positive cycle, the diode is reversed bias(open circuit) and thus current is flowing through the load resistor.
We will get the following waveform on the oscilloscope:
Biased Negative Shunt Clippers:
By now, you must have understood that an extra battery is added in series with the diode to create a Bias Clipper. As it's a negative bias, so the polarity of the battery is reversed i.e. the negative terminal of the battery is connected to the diode and the positive terminal of the battery is connected to the Vsine Source. The output is shown in the below figure:
So, that was all about the Shunt Clippers. Now let's have a look at the third tye of clippers i.e. Dual Clippers. Let's get started:
What is a Dual Clipper?
As the name depicts, the Dual Clipper is a combination of two types of Shunt Clippers i.e.
- Biased Shunt Positive Clipper.
- Biased Shunt Negative Clipper.
Now, let's move towards its simulation:
Dual Clipper Proteus Simulation
We have studied both Positive & Negative Bias Shunt Clippers in the previous section, so now we need to add both clippers in a single circuit, as shown in the below figure:
As you can see in the above figure, the circuit has four parallel branches, let's discuss them one by one:
- The First branch has an AC input source.
- The second branch has a Biased Shunt Positive Clipper i.e. Diode and a battery.
- The third branch has a Biased Shunt Negative Clipper i.e. Diode and a battery, but here the polarity is reversed.
- In the fourth branch, we have the load.
- Pop the Play button, and have a look at the output:
One can see that we got a square wave that conducts the current in both directions but in clipped form. We need Dual clippers in the place where we need to clip some part of both sides of the sinusoidal wave.
So, that's all for today. In this article, we discussed what are Shunt Clippers? what are their types? and How to simulate in Proteus? We also discussed Dual Clippers along with their implementation in Proteus ISIS. Take care!!!
Full Wave Rectification in Proteus
Hey buddies, hope you all are fine. In our previous tutorial, we studied Half Wave Rectification and have seen that it rectifies the half wave of the AC signal. Today, we are going to study Full Wave Rectification to rectify the complete AC source. We will design the simulation of the Full Wave Rectifier in Proteus software. So, let's get started:
What is Full Wave Rectification?
A comprehensive definition of full-wave rectification is:
- Full-wave rectification
is a process to convert both cycles(positive & negative) of input(sinusoidal) wave to pulsating DC
(Direct current).
We have studied in the previous lecture that Half Wave Rectifiers are used to convert only one cycle(either positive or negative) of an AC signal into a DC signal, thus dissipating the 50% energy of the overall signal. But in Full Wave Rectifiers, both cycles of the AC signal are converted into a single pulsating DC signal.
We used a single diode in our circuit to achieve half-wave rectification but for full-wave rectification, we need to create a bridge using 4 diodes. Here's the circuit diagram of Full Wave Rectification, designed in Proteus:
Why Full Wave Rectification?
Full Wave Rectification is always preferred over half wave rectification because of following factors:
- In half-wave rectification, half of the wave gets wasted as the diode suppresses the second half cycle. But if we add the diode bridge, we can easily get the complete signal i.e. both of its cycles.
- Full Wave Rectification gives higher output values with a low ripple factor.
Full Wave Rectifier Simulation in Proteus ISIS:
You can download the complete Proteus Simulation of Full Wave Rectifier, by clicking the below button:
Full Wave Rectification in Proteus
First of all, we have to pick the components from the Proteus Components Library. We are going to need these three basic components:
- Full Wave rectification bridge
- Resistor
- Alternating voltage source
- Go to the pick library button and select these components, as shown in the below figure:
- So, design the circuit for full-wave rectification in Proteus, as shown in the below figure:
- Change the value of load resistance to 500 ohms.
- Set the Vsine Frequency to 1000Hz & amplitude to 120V.
Now we are going to place an oscilloscope to monitor the input & output signals. You will find the oscilloscope in the "Virtual Instruments" section on the left bar. So, our final circuit with an oscilloscope is shown in the below figure:
- The oscilloscope settings are shown in the below figure:
The output of oscilloscope is shown in the below:
As you can see in the above figure:
- The Yellow(A Terminal) wave shows the sinusoidal wave. Whereas, the blue wave (B terminal) shows a positive half-cycle and the magenta one (C terminal) shows a negative half-cycle. And the magic is, both the outputs are direct currents and are combined in a single direction at the load resistance.
Thus, today we studied another simple Proteus experiment that shows what is full wave rectification, how to make the simplest circuit that shows the best output of full wave rectification and why we need the full wave rectification circuit. Till the next tutorial, take care!!!
Common Collector BJT Amplifier in Proteus ISIS
Hi Mentees, Welcome to a new tutorial at The Engineering Projects. Today You will unearth about Common Collector bipolar Junction Transistor Amplifiers. Before this, we learnt about two types of Configurations of Transistors named Common Emitter BJT Amplifiers and Common Base BJT Amplifiers.
In this tutorial We'll discuss about:
- Introduction of Common Collector BJT Amplifier.
- Basic Concepts for the Common Collector BJT Amplifiers.
- Implementation of Common Collector BJT Amplifiers in Proteus ISIS.
- Characteristics and advantages of Common Collector BJT Amplifiers.
So that, you can get the best understanding about the topic and its practical implementation.
Introduction
1st of all, We'll have a brief definition of the Common Collector Amplifier:
" A type of Bipolar Junction Transistor Amplifier is called Common Collector BJT Amplifiers in which Collector is common to both Base, Base region is used for input and emitter is used to take the output of the Amplifier."
It is one of the Configuration of the Transistor and is used in many kinds of circuits due to its efficiency. Other two Configurations are;
- Common Base BJT Amplifiers.
- Common Emitter BJT Amplifiers.
All of them acquire their Own Construction, characteristics and advantages as we as disadvantages. Common Collectors are also called as
Emitter follower Configuration as the emitter voltage follows the base voltage.
Basic Concepts:
It is Always useful to get core information about the circuit before its Implementation. Let's see what a Common Collector amplifiers is.
Type of transistor:
Recall that the are two types of Transistors i.e, 1. NPN 2.PNP. the Transistor we are using NPN transistor for our Experiment because in this type, the electrons are majority carries that have more mobility than holes ( majority charge carriers in PNP transistors) therefore, we get quick and easy output due to best electron flow.
Current Gain:
The current gain of this type of amplifier is also taken as the division of the Emitter current with the base current and mathematically it is stated as:
Current Gain = Emitter current/Base Current
? = IE/IB = ß + 1
Voltage Gain :
Voltage Gain of Common Collector BJT Amplifier is considered to be the unity, i.e. 1 and is obtained by the formula given below:
Voltage Gain=Vout/Vin
where in Common Collector amplifier we give the input to Base and take the output from the emitter of the transistor.
Emitter Current:
in this Configuration the Emitter current is taken as the sum of base current and collector current.
consequently, we say
Ie=Ib+Ic
we can use this equation in others ways as,
Ib=Ie-Ic
Ic=Ie-Ib
we can also say that the collector current is approximately equal to Emitter current because base is very thin region and passes a minute amount of current through it.
Implementation of Common Collector BJT Amplifier in Proteus ISIS
At the instance, we will test the circuit given in the circuit diagram in Proteus. the material for the Circuit is given below.
Material Required:
- Transistor (2N1711)
- Capacitor
- Resistor
- Vsine
- Oscilloscope
- Ground
- Take 1st four components from the "Pick device" library presented at the left corner of the screen.
- Set them at the working area according to the circuit diagram.
- Add the ground terminal by left clicking the screen >Go to Place>Terminal>Ground and add the ground Terminal.
NOTE: You can also connect just one Ground terminal to the circuit if you connect the Circuit with a wire at the bottom.
Now, the Circuit will look like this:
- Add the DC source from "Generation Mode" to just above the circuit.
Now, We need an output device to examine the output. Therefore, We'll use Oscilloscope. Choose it from "Virtual Instrument mode".
- Set the Oscilloscope just aside the circuit and Connect Channel A with input (Base) and the Channel B with the output ( Emitter).
Before Starting the simulation, I am going to change the values of the Components I used because the default values will not give us the required Output.
- we will use the 120V for the DC Power source.
- One can clearly examine that the Values of the Components are given according to the table given below:
Components |
Values |
Resistor R1 |
10ohm |
Resistor R2 |
100ohm |
Resistor R3 |
20ohm |
Resistor R4 |
100kohm |
VSine |
Amplitude=220, Frequency=1000 |
Capacitor 1 |
50m |
Capacitor 2 |
2m |
Oscilloscope |
Channel 5V, Channel B=5V, Time=0.2mS-1 |
- After setting the values you can change the value of Oscilloscope to get the required output.
NOTE: The amplifiers are sensitive to the temperature and the type of transistor used, hence their must be the practice to get the best output.
Characteristics
- The input Resistance of Common Collector Amplifiers is high.
- The power gain of this kind of amplifiers is medium.
- It has low output resistance.
- It has non-inverting effect (opposite to other two Configuration that gives the inversion of the wave).
- It has zero voltage gain.
Advantages of Common Collector BJT Amplifiers
- It is useful for the circuits where the high impedance is required.
- It is mostly used as voltage buffers as the voltage gain is unity.
- The Common Collector configuration is used in the Circuit where the engineers want the high current gain.
- Due to its high current gain, it is applied in circuits to drive heavy loads.
- We use it for voltage translation stage.
NOTE: Sometimes, It becomes the disadvantage of the Common Collector bipolar Junction Transistor Amplifier that they have no voltage Gain.
Summary:
Today, we ascertained the Basic Common Collector BJT Amplifiers, learnt some Concepts about it, saw the Implementation in Proteus ISIS, saw some characteristics and found the advantages of the Common Collector Configuration.
Common Emitter BJT Amplifier in Proteus
Hi Learners, I hope you are doing good. This lesson is about implementation of one of the types of Amplifiers i.e,
Common Emitter BJT Amplifier. But, prior to this, we'll revise some basic concepts so that it will be easy for you to understand the roots of the Experiment.
We'll talk about:
- What are Common Emitter Bi-Junction Transistors.
- Concepts of Common Emitter Bi-Junction Transistors.
- Implementation of Common Emitter BJT Amplifiers in Proteus ISIS.
- Why we use Common Emitter BJT in Amplifiers.
What are Common Emitter Bi-Junction Transistors
There are three types of Configurations of a transistor named:
- Common Emitter Configuration
- Common Base Configuration
- Common Collector Configuration
We chose the Common Emitter Configuration due to its suitability (You will learn the reason).
We can
Define Basic Common Emitter BJT Amplifier as:
"A type of amplifier circuit made by a Bi-Polar junction Transistor that uses NPN BJT Transistor, inverts the voltage output wave at 180 degree and is the one from the three basic BJT amplifier Configuration."
Recall that
A Transistor is made by combining two diodes in required manner. Hence, It there are two types of Transistors:
- NPN configuration.
- PNP Configuration.
Here N is the symbol for Negative doping and P is the symbol for positive doping.
Concepts of Common Emitter Bi-Junction Transistors
At this instance We'll look at some basic concepts, on the basis of which we chose these Components along with the values of Components of amplifier.
Current gain:
In BJT Amplifiers, current gain is the ratio of change in collector current to the change in the current of base.
mathematically, Current Gain= Change in collector current/Change in Base Current
ß=?Ic/?Ib
At the same token,
Voltage Gain:
The Voltage Gain of an amplifier is the product two Quantities. One is the ratio of output resistance of the collector to the input resistor of the base, and the other is the current gain.
Voltage Gain=ß(Rc/Rb)
During the Practical work we take AC output voltage from collector with respect to emitter and the Output of Amplifier is taken from Collector. On the other hand, the input is given to the base terminal.
It is obvious to notice that the emitter is Common to Base and Collector. It consist of Voltage divider biasing, hence one of the basic part of circuit is consist of two resistors so that their mid-point is used for supply Base Bias voltage. One more importance point to remember is gain is different from one transistor to the other.
Biasing:
Biasing is a technique to add the Battery in a circuit. It is important in Electronic devices because it establishes the correct operating point of the Transistor amplifier when it is ready to receive the signal from input and hence the plays an important role in reducing the distortion in the output.
If we look at the characteristics then we come to know that Common Emitter BJT Amplifiers has high voltage gain, the current gain is medium and the circuit has a high power gain.
Implementation of Common Emitter BJT Amplifiers in Proteus ISIS
For the practical verification of the circuit It is always Advisable to Perform it at any simulation software. Hence open Your Proteus ISIS.
Components Required:
- NPN transistor (2N171) .
- Vsine
- Capacitor
- Resistor
- DC Power source
- ground Terminal
- Oscilloscope
Procedure:
- Choose 1st four Components from the Pick Library "P" one by one by writing their name in it.
- Collect the DC power supply from "Generator mood" present on the left most tab.
- To get the Ground terminal, left Click on the working screen and go to Place>Terminal>Ground and fix it on the screen.
- Oscilloscope is present in the "Virtual Instrument Mood" on the same tab.
- Once you have chosen all the required Device then set them one by one on the Working area according to the Picture given below and connect them with the help of wires.
- At the Instance we will change the values of some devices So I have made a table for this:
-
Components |
Values |
Resistor R1 |
60ohm |
Resistor R2 |
500ohm |
Resistor R3 |
1000ohm |
Resistor R4 |
2000ohm |
Resistor R5 |
100ohm |
Oscilloscope |
A=20V, B=2V |
Vsine |
Frequency=1000Hz, Amplitude=110V |
DC source |
10V |
After substituting the value we get the prepared circuit for the amplifier as:
It seems that all the things are ready. Once you play the simulation then you can change its values and You will acquire the following output.
- Select the Current probe from the left most bar and connect them in the circuit one with the Base wire and the other with the collector.
One can find the current gain by simply putting the values in the formulas given in the concepts portion.
here,
Current gain=6.2*10-12/6.1
=1.01*10-9
as it is a ratio, hence has no unit.
At the same token,
Voltage gain=1.01*10-9*(500/2000)
=2.5*10-10
NOTE: The Gain is vary from transistor to transistor and the temperature is also an important feature. Therefore, the gain is always unpredictable.
- We got the required output in the Proteus ISIS as required.
let's find out why we used this for our experiment.
Why we use BJT in Amplifiers
Common Emitter BJT Amplifiers are important in the World of Electronics. One can get the idea of their influence by the following points:
- These Amplifiers are used in low frequency voltage amplifier.
- The are useful because of their high power gain with medium voltage and current gain hence they are cheap.
- The output impedance is high.
- It has inverting effect so can be used in the different appliances for different purposes.
In today's tutorial, We learnt what is Common Emitter BJT amplifiers, some basic concepts along with the simulation in the Proteus ISIS. We also saw why these Amplifiers are used in the real life.
The circuit and the output may vary for other circuits but don't worry about that because it is a very sensitive circuit.
Common Base BJT Amplifier in Proteus
Hi mentees, Welcome to
The Engineering Projects. If you are seeking for the Practical Implementation of
Common Base bipolar Junction Transistor amplifier then you clicked at the best website because we'll cover the basic concepts and the procedure step by step.
So, Lets start the learning.
What is Common Base BJT Amplifier?
The precise definition of the Common Base BJT Amplifier is:
"The type of Bipolar Junction Transistor Amplifiers in which Base is Common to both emitter and Collector and Current gain is taken from the Base is called Common Base bipolar Junction Transistor Amplifiers."
Recall that a transistor has three regions i.e, Base, Collector and Emitter. Hence we design our Circuit in such a way that we get the output of current from the base and get the best current gain.
Basic Concepts:
Some Important Concepts should be kept in mind so that it will become easy and interesting to Design the Circuit.
Current gain:
" The Current gain of Common base Amplifier is equal to the ratio of Current in the Collector to the Current in the Base provided by the constant voltage of base to collector."
Mathematically,
Current gain=Collector Current/Base Current
ß=Ic/Ib
Voltage Gain:
"T
he Voltage gain of the Common Base amplifier is obtain when we divide the Voltage of Collector to the voltage of emitter."
mathematically,
Voltage Gain=Voltage of Collector/Voltage of Emitter
Av=Vc/Ve
Type of Transistor:
In the Common Base amplifiers, we use the NPN transistor because in this way we get the require output more easily. In NPN transistors, majority is the electrons. The mobility of electrons is better than holes (in PNP Transistors) so they are faster.
Biasing:
Biasing is a technique to add the Battery in a circuit. It is important in Electronic devices because it establishes the correct operating point of the Transistor amplifier when it is ready to receive the signal from input and hence the plays an important role in reducing the distortion in the output.
Common base MUST correctly Biased so that the base-emitter junction will remain forward Bias.
Now, Let's move towards the practical implementation.
Implementing Common Base BJT Amplifier in Proteus ISIS
To Perform the experiment. we need the Proteus ISIS then follow the steps:
Material Require:
- Transistor (2N1711)
- Capacitor
- Alternating Current Source (Vsine)
- Resistor
- Oscilloscope
- Ground.
- Open Your Proteus software in the PC.
- Seek the Pick Library "P" button and write the name of 1st four Components one by one and select them.
- Place the current components on the working area.
- Acquire the Oscilloscope from the "Virtual Instruments mode" from the left most area and fix it just above the circuit.
- You can obtain the Ground Terminal by left click on the screen>Place>Terminal>Ground or just search it in the "Terminal mode".
- Connect all the Components through wires. The circuit looks like the image given below:
- At this instance , Change the name and values of resistors one by one by double clicking them. In this way, the circuit will work Perfectly.
- I labelled all the Resistors with different names and changed the values according to the need.
- At the same token, the name of Capacitor, battery cells and their values are also changed according to the table given below:
Components |
Values |
Resistor R1 |
400ohm |
Resistor R2 |
30ohm |
Resistor R3 |
100ohm |
Resistor R4 |
200ohm |
BAT |
50 |
BAT 1 |
200 |
CIN |
2mF |
COUT |
60uF |
Oscilloscope |
Channel A=20V, Channel B=20V, time=0.5m-1 |
VSine |
Amplitude 220V, Frequency=1000 |
- Set all the values according to table.
- Once the values are selected (except Oscilloscope) just Pop the Play button.
- You can see an Oscilloscope screen showing the waves.
- Turn of the Channel C,D to avoid distraction.
- Set the values of Oscilloscope by matching with the table.
- You will get the output just like shown in the following image:
The Yellow wave (channel A) indicates the input wave were as the Blue Wave (Channel B) indicates the output ( Amplified) wave.
Hence by If we choose the Components and there value carefully, we get the best output.
Lets Calculate the Current gain then Voltage Gain.
I am using the previously Described precepts to calculate the Quantities:
- Connect the DC Ammeter from the "Generation Mode" and Connect one with the Base of transistor and one with the Collector.
- When we play the Simulation then we get the following Output:
Applying the values into the formula we get,
ß =-1.43/-0.07
=20.4
As it's a ratio so it doesn't have any unit.
Moving towards the Voltage Gain,
- Take the "DC Voltmeter" from the same Portion and connect one Voltmeter with CIN capacitor and one with the COUT Capacitor. Note than the Voltmeter is always Connected in parallel to the required Components.
At the moment, When we start the simulation, we get the following output:
Applying these Values for Av,
Av=53.1/3.75
=14.16
So that the required Quantities are obtained.
Characteristics of Common Base BJT Amplifiers:
- It has High Voltage Gain.
- The Current Gain of Common Base BJT Amplifiers is Medium.
- We get High power Gain in this type of Amplifier.
- Common Base Amplifier does not have any reversal effect between input and output waves.
- The Input and Output resistance of the Common Base Amplifier is Medium.
Advantages:
- We Get the inverted output wave that may be useful in many electronic devices.
- The Input Impedance is Low.
- It is useful due to its high power gain.
- The output Impedance is High for Common Base Bipolar Junction Transistor Amplifiers.
- The Output Impedance is high.
- When we need Impedance matching then CB Amplifiers are useful because we can control the input Impedance.
- It Provides the constant Current Gain therefore can be used as buffer amplifiers.
Thus Today we Learnt about the Common Base Bipolar Junction Transistor Amplifiers, cleared Some Basic Concepts about them, Implement the Amplifiers in Proteus ISIS and read about the characteristics and advantages of the Common Base Bipolar Junction Transistors Amplifiers.
Series Clippers and its types in Proteus
Hello friends, I hope you all are having fun. In today's tutorial, we will have a look at Series Clippers & their types in detail, we will also implement the simulations of Series Clippers in Proteus software. In the next article, we will discuss the next two types of Clippers i.e. Shunt Clippers & Dual Clippers. Today, We are going to learn:
- What is a Clipper?
- What are the types of Clippers?
- Series Clippers Simulations in Proteus.
So, let's get started:
What is a Clipper???
- Clipper (also known as Limiter) is an electronic circuit, which clips or limits the amplitude(positive, negative or both) of an AC source wave.
- Diodes are normally used for designing Clippers and such circuits are normally referred as Diode Clipping Circuits (Diode Limiting Circuits).
- Here's an example of a Diode Clipping Circuit, where we are clipping the positive amplitude of the AC pulse:
- As you can see in the above figure, we are clipping the positive side but if we want to clip the negative side, we just need to reverse the diode polarity.
- Clippers are normally used for protection purposes i.e. if there are some voltage spikes then clip it to secure home appliances.
- Half wave Rectifier is also a type of clipper as it clips one side of the AC pulse to 0V.
Now, let's have a look at different types of clippers:
Types of Clippers
In the previous section, we have had a complete understanding of what is clipper. Now let's have a look at three different types of Clippers:
- Series Clippers.
- Positive.
- Positive with bias.
- Negative.
- Negative with bias.
- Shunt Clippers.
- Positive.
- Positive with bias.
- Negative.
- Negative with bias.
- Dual (Combination) Clippers.
As today's topic is about Series Clippers, so let's implement them in Proteus ISIS:
Series Clippers Simulation in Proteus
- First of all, we need to open the Proteus ISIS software to design our circuit.
- Select the following components from the "Pick Components" section:
- Diode
- Resistor
- Vsine source
- Battery
- So, first of all, let's place our AC source Vsine and GND in the proteus workspace.
- Double-click on the Vsine source and change the value of amplitude and frequency to 11V
and 1000Hz
respectively.
Our power source is ready, now let's design different types of Series Clippers in proteus:
1. Positive Series Clippers in Proteus ISIS
- In Positive Series Clipper, the positive half cycle of the wave is clipped(removed).
- In the positive clipper circuit, the arrowhead of the diode points towards the input source.
- So, let's design the circuit as shown in the below figure:
- As we can see in the above figure, diode D is connected in series with the load
resistor and is pointing towards the AC source.
- Double-click at the resistor and change its value from 10k ohm to 500 ohms.
- We'll also add the DC voltmeter to show the difference between biased and unbiased circuit
- We've connected terminal A of the oscilloscope with the AC Source(Vsine) and terminal B is placed after the diode.
- This is the time to pop the play button and set values of the oscilloscope according to the below table:
Components |
Values |
Channel A |
20V |
Channel B
|
20V
|
Time |
0.2ms-1 |
- If everything goes fine, we will get the required output as shown in the figure:
- In the above figure, the Yellow curve is showing the input voltage, while the blue line is the output voltage(after the diode) received by the load resistor.
- We can clearly see that the positive side of the AC source waveform is now clipped and that's why it's called Positive Series Clipper.
2. Positive with Negative Bias Series Clipper
The Positive Series Clipper removes the positive side of the curve completely but what if we want to clip only 25% of the positive side? In that case, we use positive with Negative Bias Series Clipper. It's circuit is shown in the below figure:
As we can see in the above figure, we have added an extra element called Battery.The rest of the circuit is same as that of the Positive Series Clipper i.e. the diode is
pointing towards the current source and is in series with the resistor.
The volt meter is giving us -5V, where the 5V is coming from the added battery and the negative sign shows that the circuit is negative bias.
- The output for the circuit on the oscilloscope is shown below:
As you can see in the above figure, the output curve is slightly clipped at the top. If we reduce the battery voltage, the clipping of the curve increase and at 0V the complete positive part will be clipped out(same as Positive Series Clipper).
If you want a clipper with a positive bias, simply change the direction of the battery. Connect the negative terminal of the battery with the negative side of the diode. It's a task, post your results in the comments.
3. Negative Series Clipper in Proteus
- In a Negative Series Clipper, the negative half cycle of the wave is clipped(removed).
- In negative clipper circuits, the arrowhead of the diode points towards the load resistor.
- Here's the circuit diagram of the Negative Series Clipper:
- The circuit is the same as that of the Positive Series Clipper with a slight difference in the direction of the diode.
- The output of the oscilloscope for the series circuit of negative clippers shows us that the negative side of the wave is clipped:
4. Negative with negative bias Series Clippers
As we discussed, the whole negative part of the signal gets clipped in the Negative Series Clipper. So, in order to clip a certain amount of negative side, we need to add a new battery source and this model is called Negative with Negative Bias Series Clipper. It's circuit diagram is shown in the below figure:
As we can see in the above figure, the diode is pointing towards the load resistor. We have connected the negative terminal of the battery with the positive side of the diode. Here are the results from the oscilloscope:
So, that was all for today. In this article, we studied the series clipper and its types, along with their simulations in Proteus software. I hope you have enjoyed today's lecture. Let me know your feedback/queries in the comments. Have fun!!!