DIFFERENTIAL AMPLIFIER using MOSFET, Modes of operation,
The MOS differential pair with a common-mode input voltage ,Common mode rejection,gain, advantages and disadvantages.
Reduced channel length cause departures from long channel behaviour as two-dimensional potential distribution and high electric fields give birth to Short channel effects.
A simple N-channel MOSFET can be used as a diode, Switch and Active resistor. This presentation is a part of course of Analog CMOS Design, based on textbook of same title by Allen Holberg.
Reduced channel length cause departures from long channel behaviour as two-dimensional potential distribution and high electric fields give birth to Short channel effects.
A simple N-channel MOSFET can be used as a diode, Switch and Active resistor. This presentation is a part of course of Analog CMOS Design, based on textbook of same title by Allen Holberg.
Field Effect Transistor, JFET, Metal Oxide Semiconductor Field Effect Transistor, Depletion MOSFET, Enhancement MoSFET, Construction, Basic operation, Regions of Operation, Drain Characteristics, Transfer Characteristics, Biasing, Non-Ideal Characteristics of E-MOSFET, DC Analysis, AC equivalent circuit and Parameters, E-MOSFET as an Amplifier, AC analysis, MOSFET as a Switch, MOSFET as a diode, MOSFET as a resistor, High frequency equivalent circuit, Miller Capacitance, Frequency Response, NMOS and CMOS inverter
SHORT-CHANNEL EFFECTS
A MOSFET is considered to be short when the channel length ‘L’ is the same order of magnitude as the depletion-layer widths (xdD, xdS). The potential distribution in the channel now depends upon both, transverse field Ex, due to gate bias and also on the longitudinal field Ey, due to drain bias When the Gate channel length <<1 m, short channel effect becomes important .
This leads to many
undesirable effects in MOSFET.
The short-channel effects are attributed to two physical phenomena:
A) The limitation imposed on electron drift characteristics in the channel,
B) The modification of the threshold voltage due to the shortening channel length.
In particular five different short-channel effects can be distinguished:
1. Drain-induced barrier lowering and “Punch through”
2. Surface scattering
3. Velocity saturation
4. Impact ionization
5. Hot electrons
Using Chebyshev filter design, there are two sub groups,
Type-I Chebyshev Filter
Type-II Chebyshev Filter
The major difference between butterworth and chebyshev filter is that the poles of butterworth filter lie on the circle while the poles of chebyshev filter lie on ellipse.
Introduction
Band Pass Amplifiers
Series & Parallel Resonant Circuits & their Bandwidth
Analysis of Single Tuned Amplifiers
Analysis of Double Tuned Amplifiers
Primary & Secondary Tuned Amplifiers with BJT & FET
Merits and de-merits of Tuned Amplifiers
https://www.udemy.com/vlsi-academy
http://vlsisystemdesign.com/noise_margin.php
Noise margin is the amount of noise that a CMOS circuit could withstand without compromising the operation of circuit. Noise margin does makes sure that any signal which is logic '1' with finite noise added to it, is still recognised as logic '1' and not logic '0'. It is basically the difference between signal value and the nosie value.
Field Effect Transistor, JFET, Metal Oxide Semiconductor Field Effect Transistor, Depletion MOSFET, Enhancement MoSFET, Construction, Basic operation, Regions of Operation, Drain Characteristics, Transfer Characteristics, Biasing, Non-Ideal Characteristics of E-MOSFET, DC Analysis, AC equivalent circuit and Parameters, E-MOSFET as an Amplifier, AC analysis, MOSFET as a Switch, MOSFET as a diode, MOSFET as a resistor, High frequency equivalent circuit, Miller Capacitance, Frequency Response, NMOS and CMOS inverter
SHORT-CHANNEL EFFECTS
A MOSFET is considered to be short when the channel length ‘L’ is the same order of magnitude as the depletion-layer widths (xdD, xdS). The potential distribution in the channel now depends upon both, transverse field Ex, due to gate bias and also on the longitudinal field Ey, due to drain bias When the Gate channel length <<1 m, short channel effect becomes important .
This leads to many
undesirable effects in MOSFET.
The short-channel effects are attributed to two physical phenomena:
A) The limitation imposed on electron drift characteristics in the channel,
B) The modification of the threshold voltage due to the shortening channel length.
In particular five different short-channel effects can be distinguished:
1. Drain-induced barrier lowering and “Punch through”
2. Surface scattering
3. Velocity saturation
4. Impact ionization
5. Hot electrons
Using Chebyshev filter design, there are two sub groups,
Type-I Chebyshev Filter
Type-II Chebyshev Filter
The major difference between butterworth and chebyshev filter is that the poles of butterworth filter lie on the circle while the poles of chebyshev filter lie on ellipse.
Introduction
Band Pass Amplifiers
Series & Parallel Resonant Circuits & their Bandwidth
Analysis of Single Tuned Amplifiers
Analysis of Double Tuned Amplifiers
Primary & Secondary Tuned Amplifiers with BJT & FET
Merits and de-merits of Tuned Amplifiers
https://www.udemy.com/vlsi-academy
http://vlsisystemdesign.com/noise_margin.php
Noise margin is the amount of noise that a CMOS circuit could withstand without compromising the operation of circuit. Noise margin does makes sure that any signal which is logic '1' with finite noise added to it, is still recognised as logic '1' and not logic '0'. It is basically the difference between signal value and the nosie value.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Level sensitive scan design(LSSD) and Boundry scan(BS)Praveen Kumar
This presentation contains,
Introduction,design for testability, scan chain, operation, scan structure, test vectors, Boundry scan, test logic, operation, BS cell, states of TAP controller, Boundry scan instructions.
This ppt describes about,
introduction of fuses, construction, Important terms, advantages and disadvantages, desirable characteristics of fuse element, Current time characteristics, Fuse types - Low voltages fuses and High voltage fuses, Semi enclosed rewirable fuse, HRC cartridge fuses - parts, operation, pros and cons, High voltage fuses and its types, selection of fuses, discrimination
Introduction of SCADA, Architecture of SCADA, Software and hardware architecture, Components of a SCADA system, Functions of SCADA, Alarms and events, alarm logging, comparision between scada and DCS
SPICE LEVEL I/LEVEL II/LEVEL III AND BSIM MODELSPraveen Kumar
SPICE LEVEL I/LEVEL II/LEVEL III AND BSIM MODELS
SPICE introduction
working
adaptions
detailed discussion on each models
SPICE Modeling in BSIM
features
bulk voltage on large signal model
velocity saturation
weak inversion operation
impact ionization
Finite word length of IIR filters Limit cycles due to product round-off error...Praveen Kumar
Finite word length of IIR filters Limit cycles due to product round-off errors and other non-linear characteristics
Limit cycles due to round-off errors
infinite precision
round off
truncation
An Example
MATLAB Codes
Inference
Other non-linear Characteristics
Jump Phenomenon
Subharmonic Response
Effects of product round-off errors
SOLAR POWER generation using solar PV and Concentrated solar power technologyPraveen Kumar
Concentrated Solar Power Technology
Power Tower Systems
Parabolic Trough Systems
Solar Dish Systems
Compact Linear Fresnel
Types, working, pros &cons
Scope in INDIA
Using Photo-Voltaic cells
-Working of PV Cells
-Considering different PV materials
-Efficiency, Comparing modules manufactured by different companies
-MPPT
- algorithms
-A view of different inverter topologies used
pyrheliometer
SELECTION OF DRIVES AND CONTROL SCHEMES FOR MACHINE TOOLS Praveen Kumar
SELECTION OF DRIVES AND CONTROL SCHEMES FOR MACHINE TOOLS
Machine tools and drives
Horse power requirement for driving the machine tools
MOTOR REQUIREMENTS FOR MACHINE TOOLS.
SELECTION OF MOTORS
Speed control of Drill press
Application of Motors to Planers, Shapers
Reversible motor drive quick return mechanism
GRINDING MACHINES
VFD
Sorting
Performance parameters
Insertion Sort
Technique
Algorithm
Performance with examples
Applications
Example Program
Shell Sort
Technique
Algorithm
Performance with examples
Applications
Example Program
Vehicle safety system
it covers
hydraulic brakes
working of drum ,disk brakes
abs
airbags
ESP/ESC(electronic stability programme)
future trends in safety systems
cruise control
ACC
introduction, types & structure of MOSET ,turn ON and OFF of device, working, I-V characteristics of MOSFET,Different regions of operations,applications, adv & disadvantages
Interfacing GPS with 8051 and displaying the output data in NMEA format from the gps module to 8051 microcontroller and finally displaying the latitude and longitude information also the date and time in a LCD display.
REVERSE POWER RELAY for solar PV systemsPraveen Kumar
this presentation gives an idea about designing a device using microcontroller that detects the reverse power flow from solar pannels to the grid when the load is less.
Digital Voltmeter, Digital Ammeter and Digital MultimeterPraveen Kumar
This ppt deals with Digital meters,the digital components used in them,principle behind the working of Digital Voltmeter(DC) Digital Voltmeter(AC) and mechanism of Measurement of Current and Measurement of Resistance. Finally A complete DMM also the Measurement of hfe. A small project on constructing digital voltmeter and ohmmeter using Arduino.
NO MICROCONTROLLER is used in making of these autonomous robot, we have just used only the operational amplifier as a controller and achieved the bot.we have made 2 bots Line follower and light follower with simulations in proteus and hardware implementation of these bots. Also made a wireless light controlled bot using the same concepts.Hope this presentation will be much helpful for your mini projects. Do leave some comments. Thank u.
Ventilating systems for electrical machinesPraveen Kumar
this presentation is about types of ventilation given to the electrical machines,an analysis for the best type,future improvements,and their importance in electrical machines
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
2. Differential amplifier
• Amplifies the difference between the input signals
INPUTS:
Differential input:
Vid = Vi1-Vi2
Common input:
Vic=( Vi1+Vi2)/2
OUTPUTS:
Differential output:
Vod = Vo1-Vo2
Common output:
Voc=( Vo1+Vo2)/2
3. Why differential amplifiers are
popular?
• Less sensitive to noise(CMRR>>1)
• Biasing:
1) Relatively easy direct coupling of stages
2) Biasing resistor doesnot affect the
differential gain(no need for bypass capacitor)
6. Regions of operation
• Cut off region- VGS ≤ Vt
• Active region- VDS ≤ VOV
• Saturation region- VDS ≥ VOV
TO DERIVE DRAIN CURRENT EQUATION
|Q|/unit channel length = Cox W VOV
Drift velocity= μn|E|= μn (VDS/L)
The drain current is the product of charge per unit length and drift velocity
ID=[( μnCox)(W/L) VOV] VDS
ID=[( μnCox)(W/L) VGS-Vt] VDS
ID=[kn’(W/L) VGS-Vt] VDS
Replacing VOV by (VOV-(1/2) VDS)
ID=kn’(W/L) (VOV-(1/2) VDS) VDS
At saturation mode, VDS ≥ VOV,
ID=(1/2) kn’(W/L)V2
OV
8. Operation with common mode input
• The two gate terminals are connected to a
voltage VCM called common mode voltage.
• So VG1 = VG2 =VCM
• The drain currents are,
• Voltage at sources, will be
2
21
21
I
II
QQ
DD
GSCMs Vvv
9. • Neglecting the channel length modulation and
using the relation between VGS and ID is,(at
saturation)
• Where,
W=width of the channel
L=length of the channel
VGS =gain to source voltage
Vt =threshold voltage
Kn
’ = µn Cox
2'
)(
2
1
tGSnD VV
L
W
kI
10. Overdrive Voltage
• Substituting for ID we get,
• The equation can be expressed in terms of
overdrive voltage as, VOV = VGS -VT .
• overdrive voltage is defined as VGS-VT when Q1
and Q2 each carry a current of I/2.
• Thus In terms of VOV ,
2'
)(
2
1
2
tGSnD VV
L
W
k
I
I
2'
)(
2
1
2
OVn V
L
W
k
I
L
W
k
I
VVV
n
tGSOV
'
11. Common mode rejection
• Voltage at each drain will be,
• Since the operation is common mode the voltage
difference betwee.n two drains is zero.
• As long as, Q1 and Q2 remains in saturation region
the current I will divide equally between them.
And the voltage at drain does not changes.
• Thus the differential pair does not responds to
common mode input signals.
DDDDDD RIVvv 21
12. Input common mode range
• The highest value of VCM ensures that Q1 and
Q2 remains in saturation region.
• The lowest value of VCM is determined by
presence of sufficient voltage VCS across
current source I for its proper operation.
• This is the range of VCM over which the
differential pair works properly.
DDDtCM R
I
VVv
2
(max)
)((min) tGStCSssCM VVVVVv
13. PROBLEM based on common mode:
For an NMOS differential pair with a common-mode voltage Vcm
applied as Shown in Fig.
Let Vdd=Vss=2.5V,Kn’(W/L)=3(mA/V2),Vt =0.7V,I=0.2mA,RD =5KΩ and
neglect channel length modulation.
a)Find Vov and VGS for each transistor.
b)For Vcm =0 find Vs,iD1,iD2,VD1 and VD2.
c)For Vcm =+1V.
d)For Vcm =-1V.
e)What is the highest value of Vcm for which Q1 and Q2 remain in
saturation?
f)If current source I requires a minimum voltage of 0.3v to operate
properly, what is the lowest value allowed for Vs and hence for Vcm ?
17. Differential Amplifier – Common
Mode
Because of the symmetry, the common-mode circuit breaks into two
identical “half-circuits” .
18. Differential Amplifier – Differential
Mode
Because of the symmetry, the differential-mode circuit also breaks into two
identical half-circuits.
19. OPERATION OF MOS DIFFERENTIAL
AMPLIFIER IN DIFFERENCE MODE
Vid is applied to gate of Q1 and gate of Q2 is grounded.
Applying KVL,
Vid = VGS1 - VGS2
we know that,
Vd1 = Vdd - id1RD
Vd2 = Vdd - id2RD
case(i)
Vid is positive
VGS1 > VGS2
id1 > id2
Vd1 < Vd2
Hence, Vd2 - Vd1 is positive.
20. case(ii)
Vid is negative
VGS1 <VGS2
id1 < id2
Vd1 > Vd2
Hence, Vd2 - Vd1 is negative
Differential pair responds to difference mode or
differential input signals by providing a
corresponding differential output signal between
the two drains.
21. If the full bias current flows through the Q1 , VG2 is reduced to Vt
, at which point VS = - Vt , id1 = I.
I =
1
2
kn’ (
𝑊
𝐿
)(𝑉𝐺𝑆1 − 𝑉𝑡)2
by simplyfication, VGS1 = Vt+ 2𝐼/kn’(
𝑊
𝐿
)
But, VOV = 𝐼/kn’(
𝑊
𝐿
)
hence, VGS1 = Vt+ 𝟐 VOV
Where, kn’-process transconductance parameter which is the product of electron
mobility( µ 𝑛) and oxide capacitance (𝐶 𝑜𝑥).
where VOV is the overdrive voltage corresponds to the drain current of I/2.
22. Thus the value of Vid at which the entire bias current I is
steered into Q1 is,
Vidmax = VGS1 +VS
= Vt+ 2 VOV - Vt
Vidmax = 2 VOV
(i) Vid > 2 VOV
id1 remains equal to I
VGS1 remains Vt+ 2 VOV
VS rises correspondingly(thus keeping Q2 off)
(ii)Vid ≥ - 2 VOV
Q1 turns off, Q2 conducts the entire bias current I. Thus
the current I can be steered from one transistor to other by
varying Vid in the range,
- 2 VOV ≤ Vid ≤ 2 VOV
Which is the range of different mode operation.
23. Advantages
• Manipulating differential signals
• High input impedance
• Not sensitive to temperature
• Fabrication is easier
• Provides immunity to external noise
• A 6 db increase in dynamic range which is a
clear advantage for low voltage systems
• Reduces second order harmonics
25. Applications
• Analog systems
• DC amplifiers
• Audio amplifiers
- speakers and microphone circuits in
cellphones
• Servocontrol systems
• Analog computers