Electronics part-2

Topic includes

- Assignment of Electronics 

- Logic gates
- Two conversions
- CMRR

- Wave shaper

- Multivibrator

- Oscillator and alternator

- Voltage and power amplifier

• Assignment of Electronics

Logic gates

Logic gate is a digital circuit which perform the logic operation between the applied in input across it.

The input are always given in the form of binary digits which are 0 and 1.

0 is used for low voltage and one is used for high voltage.

0 means false and 1 means true.

Truth table

The table shows all corresponding output for all corresponding inputs of a logic gate.

Any gate has one, two or more inputs but output is always one.

Not gate

It is the only gate which has single input and single output.

And gate

It shows the product of two expression

  A.B

Or gate

It shows the submission of two expressions

A+B

Nand gate

It shows the output which is opposite of and gate.

Nor gate 

It shows the output which is opposite of or gate.

Diagram shows all gates with their truth table 

Two conversions  are .

Click on image for preview

Hexadecimal to octal

Decimal to binary

CMRR common mode rejection ratio 

CMRR of a differential amplifier is a metric used to quantify the ability of a device to reject common mode signals.

Wave shaper

The process by which a non sinusoidal wave form are alter by passing through the circuit element diode resistor inductor and capacitor is gold wave shaping circuit.

The wave shaping is used to perform such 

operations..

-to generate one wave from another.

- to cut off positive negative portion of input wave.

- the waveshaper circuit are used to change the shape of the circuit to the desired shape.

-to hold the wave from to particular DC level, the wave shaping is important most of the signal processing signals and is performed by the circuit known as differentiators clipper and clamper.

Two types are 

Linear wave shapes

 The linear wave shaping circuits are passive components such as registers, inductors and capacitors.

the basic property of this circuit is that they do not change the shape of wave but just change the face and amplitude.

For example high pass filter, low pass filter, attenuator.

Non linear waves shapes

The circuit consists of resistor inductor capacitor diode zener diode.

In this circuit when input is sinusoidal wave but output is different.

For example clipper clamper, comparator.

R - C circuit as a Differentiator

R - C circuit as a integrator

Multivibrator

The electronic circuit which can generate the square waves is known as multivibrator.

Every multivibrator have two transistor each of them act like switch. Hence,  two transistors that supply on or off alternatively.

There are three types of multivibrators

1. Astable multivibrator or free running multivibrator.

2. Bistable multivibrator

3. Monostable multivibrator

Astable multivibrator

Construction

Multivibrator that generates a square wave of its own is known as a stable multivibrator.

It requires DC power source of its operation. In this two identical transistors are used point the output it of the first is coupled to the input of the next stage through capacitor C1 and the output of second stage is coupled to the input of first stage through capacitor C2.

It does not require any external triggering pulse to change the state.

Working

Case1

When the power supply is turned on, the positive supply VB is given to the base of the transistor. The current source, the collector terminal of both the transistors t1 and t2. Due to some mismatch in parameters the current IC1 is greater than IC2.

it causes the collector voltage of Stephen is low because the IC one is high. This low voltage is provided at the the base of the transistor T2 then and the collector current is also low. So this fall in voltage causes the collector current in IC1 to decrease and collector voltage of T2 increases. This rise in voltage is coupled to the base T1 .

As a result voltage t1 increases and t2 starts conducting whereas T2 is off.

Case 2 

Under this condition one of the capacitor even is connected to the ground through on transistor t1 and other end is connected to the supply vbb through register R. now the capacitor charge through the vbb as we know that the capacitor also connected to the base of the transistor T2.

through E2 capacitor will discharge and t2 starts conducting the collector voltage of T2 decreases this fall in voltage  is connected to the base of t1. this fall in voltage produces low current at the current collector terminal of t1. If IC1 is low then the collector voltage t1 is high.

That high voltage is connected to the base of T2. So at that case T2 is on and t1 is off.

Above diagram shows all multivibrator diagrams with square wave output.

Difference between oscillator and alternator

01 What type of Device is it?
  An alternator is a mechanical device.
An oscillator is an electronic device.

02 Definition
The mechanical device which converts mechanical energy to the AC supply electrical energy is called the ‘Alternator’.
The electronic device which converts DC energy into the AC energy is known as the ‘Oscillator’.

03 Functionality Difference
An alternator can produce the high-frequency (more than 50Hz) oscillations according to prime mover rpm.
The oscillator can produce the high-frequency oscillations with the several MHz frequencies.

04 Nature of Device
It is a rotating and energy converting device. It is a non-rotating and frequency generating device.

05 Working Principles
The alternator operates on the principle of Electromagnetic Induction.
An Oscillator operates on the principle of the Oscillation.

Information about Voltage And Power Amplifier

Voltage Amplifier

A voltage amplifier is an amplifier that amplifies given voltage for a larger voltage output. It is characterized by a high input impedance and low output impedance.

This is useful for reading and adapting small signals such as boosting an audio signal before sending it on its way to speakers.

 The voltage amplifier is a form of the common emitter amplifier which relies on the transistor, the amplification of voltage is dependent on the ratio of resistors on the collector and emitter of this transistor.

 Need To Know About Voltage Amplifier

The voltage amplifier amplifies the voltage or increases the voltage level of a signal.
The voltage amplifier can work with low magnitude signal.
In voltage amplifier, the amplitude of input A.C signal is small.
The transistor used in the voltage amplifier has a thin base because it does not handle large current.
The output impedance of the voltage amplifier is very high, about 12 kilo-ohm.
The collector current of the voltage amplifier is very low up to 1 mA.
The transistor used can dissipate less heat produced during its operation.
The physical size of transistor used is usually small and is known as low or medium power transistor.
RC coupling is used in voltage amplifier.
In power amplifier, the collector load has low resistance, typically 5Ω to 20Ω.

Power Amplifier

Power amplifier as the name suggests is an amplifier that makes a given input current higher. It is characterized by a low input impedance and high output impedance. It is usually used in the last output stages of a circuit.
Examples include: audio power amplifiers, servo motor controllers, push-pull amplifiers and RF power amplifiers.

Need To Know About Voltage Amplifier

The power amplifier amplifies the power of a signal.
The input signal of the power amplifier must have a high magnitude.
In power amplifier the amplitude of input A.C signal is large.
The transistor used in the power amplifier has a thick base because it handles the very large current.
The output impedance of the power amplifier is very low, up to 200 ohm, so that it can deliver a high current.
The collector current of the power amplifier is high greater than 100 mA.
The transistor used can dissipate more heat produced as compared to voltage amplifier during its operation.
The physical size of transistor used is usually large and is known as power transistor.
Transformer coupling is used in power amplifier.
In voltage amplifier, the collector load has high resistance, typically 4Ω to 10kΩ.