Transistors and Digital Logic Gates

Flow and Pressure

To begin this we will take a brief excursion into electrical engineering by way of plumbing! 

Figure 1. Click to open or close the valve. See what happens to the pressure.

Consider the apparatus in Figure 1. We have a water reservoir and two large pipes joined by a smaller, constricted pipe. The upper pipe is connected to the reservoir and the lower pipe is open. A valve can control flow through the lower pipe. Two pressure gauges measure the pressure in the pipes.

The reservoir is drawn to fit the page; imagine that its capacity is very large -- on the order of that of a municipal water system. In other words, the reservoir will provide water at constant pressure and a high flow rate for a very long time.

When the valve is closed, the pressure is equal on both sides of the constriction. Click on the valve wheel to open or close the valve and observe what happens to the pressure.

When the valve is open, water escapes from the system through the open lower pipe, and the pressure in the lower pipe drops because the rate of supply is limited by the constriction. The pressure above the constriction remains high because of the reservoir supply. In other words, there is a pressure drop across the constricted pipe. The pressure drop occurs only when there is flow through the constriction; when there is no flow, the pressure is constant throughout.

 

Electrical Pressure

Electricity has "pressure" just as water does. Electrical pressure, or electromotive force, is measured in Volts and is often called voltage.  The volume of electrical flow is measured in Amperes and is called current.

A switch is an all-or-nothing device like the valve in Figure 1. There are devices that can impede the flow of electricity, similar to the constricted pipe in Figure 1. These are called resistors and they appear as a sawtooth line in a schematic diagram. The relationship among resistance, current and voltage is described by Ohm's Law,which we will not study here.

What is important to students of digital logic is this: If no current is flowing through a resistor, the voltage at the two ends will be the same; if current is made to flow through the resistor, there will be a voltage drop across the resistor. This is analogous to the pressure drop across the constricted pipe of Figure 1. The pressure drops only when water is flowing.

Consider an electric circuit that is conceptually similar to Figure 1.

Figure 2. Click on the switch to change the state of the circuit.

The circuit of Figure 2. has a switch, a resistor, and two LEDs. The resistor is shown as a sawtooth line. The symbol V_cc indicates the supply voltage. Later we will learn that this supply voltage is common to the collectors of our transistors, hence the name. The striped triangle at the bottom of the diagram is the "ground" symbol and indicates the return to the power source.

In digital logic, it is common to let a "high" voltage, that is a voltage nearly equal to V_cc indicate a logical one, and a "low" voltage -- a voltage near zero -- indicate a logical zero. In the initial state, with the switch open, both LEDs in Figure 2. are on indicating a logical value of one.

Now click on the switch to close it. Closing the switch allows current to flow from V_cc to ground. Because current is flowing, there is a voltage drop across the resistor. The voltage at the lower end, labeled "Output," becomes approximately zero as shown by the extinguished LED. The upper LED remains on because it is connected to V_cc. In future circuits, we will not bother to show the upper LED because it is on all the time.

An important thing to notice about Figure 2. is that the output is true, or one, when the switch is open. This circuit is an inverter; it computes the Boolean NOT function.

 

Transistors as Switches

At last we are ready to start using transistors! A transistor is an electronic device with three elements called the base, the collector, and the emitter. Transistors can function as analog devices and are used in that way in radios, amplifiers, and similar gear. By choosing suitable transistors and providing suitable inputs, they can also function as digital devices -- switches that are either on or off.

Transistors have the property that if a suitable voltage is applied to the base, current can flow between the collector and the emitter. This is exactly like the mechanical switches we've been using except that we control the switching action with voltage instead of mecahnical motion. Switches made in this way can operate at electronic speeds instead of mechanical speeds. The switching speed of a typical transistor is a few nanoseconds -- a few billionths of a second. That's how computers can operate as fast as they do.

Replacing the mechanical switch with a transistor gives the circuit of Figure 3.

Figure 3. An inverter. Click on the pushbutton to change the voltage at the base of the transistor.

The circular element in the schematic diagram represents a bipolar transistor. (Other kinds of transistors can be used in digital logic; they have different symbols.) The transistor has three connections: the collector, the emitter, and the base. When the voltage at the base of the transistor is high enough, current can flow from the collector to the emitter. When the voltage at the base is near zero, no current can flow. The transistor acts like a switch.

The pushbutton in the diagram can be used to apply or remove voltage at the base of the transistor. Click on the pushbutton and observe what happens. When voltage is present at the base of the transistor, current flows from collector to emitter, then to ground, and there is a voltage drop across the resistor. The voltage at the output drops to near zero. Removing the voltage at the base stops the current flow and the output voltage rises to be equal to V_cc.

A transistor used in this way is an amplifier as well as a switch. A voltage lower than V_cc is enough to make the transistor switch on; very little current flows from the base to ground through the emitter. A much larger current flows from collector to emitter and then to ground. The transistor is a current amplifier, but the important part of the circuit is the voltage change at the output, from near V_cc when the transistor is switched off to near zero when the transistor is switched on.

Like the circuit in Figure 2, this circuit is an inverter. The output is high when the input is low and vice-versa. This circuit computes the Boolean NOT function. 

NAND and NOR Gates

Figure 4. A NAND gate. The value of the output is controlled by the two inputs A and B.

The circuit of Figure 3 illustrates some important concepts, but it isn't very interesting. We can do more if we build circuits with two or more inputs. Figure 4. shows a NAND gate. The name NAND is a contraction of not-and. Current can flow, and produce a voltage drop across the resistor, only if both transistors are conducting. Having either transistor switched off is enough to block current flow and hold the output high.

For purposes of this lecture we are going to define a "high" voltage -- a voltage near V_cc -- to indicate a logical 1, or true. A low voltage, near zero will indicate a logical 0, or false. (It is possible to reverse those definitions so long as one is consistent. We will not studynegative logic circuits here.)

 

  Table 1. NAND

	A	B		X
	0	0		1
	0	1		1
	1	0		1
	1	1		0

 Using 1 to represent a high voltage and 0 for low, we can write a truth table that describes the behavior of the NAND gate. Columns A and B of the table represent the two inputs, A and B, of theNAND gate. The X column shows what the output will be for each combination of A and B. The truth table for the Boolean NAND function appears at the left. Experiment with the circuit in Figure 4 and verify that it actually computes the NAND function.

It is clear from the schematic diagram that we could build a NAND gate with more than two inputs. Adding a third transistor in series gives a three-input NAND. As an exercise, write the truth table for a three-input NAND gate. You will have inputs A, B, and C and output X.

Figure 5. A NOR gate. The transistors are connected in parallel.

The NAND gate has its transistors connected in series. Recall from the Electric Circuits Web Lecture that switches can be connected in series or parallel. If we connect transistors in parallel as shown in Figure 5, applying a signal to the base ofeither transistor is sufficient to allow current to flow through the resistor and pull the output voltage to near zero. This is the NOR gate. The name NOR is a contraction of not-or.

  Table 2. NOR

	A	B		X
	0	0		1
	0	1		0
	1	0		0
	1	1		0

Let's look at the truth table for the NOR gate. Again we have inputs A and B and output X. This time, X is true, or 1, only when A and B are both 0. Another way of saying that is that X is 1 when neither A nor B is true. Experiment with the circuit to verify that it computes the function given in Table 2.

As with the NAND gate, the NOR gate can be extended to more than two inputs by adding more transistors, this time in parallel.

Figure 5 makes it obvious why the power supply voltage is called V_cc. It is connected in parallel, or in common, through the resistor to the collectors of both transistors. In a complex digital logic circuit, the same power supply voltage will be connected in common to all the gates.

About now you may be wondering why we started with NAND and NOR gates instead of the more familiar AND andOR functions. There are two reasons, one founded in electrical engineering and one founded in logic.

Although the gates shown here are simplified by comparison to the actual construction of integrated circuits, you could go to an electrical engineering lab and build the circuits of Figures 3, 4, and 5. If you did, they would function just as the animations demonstrate. These three gates, NOT, NAND, and NOR are the simplest possible digital logic gates. Each has only one transistor per input. Any other gate, and in particular the non-inverting gates AND and OR require more transistors.

Even more important is the fact that NAND and NOR are complete. This means that any other digital logic gate can be constructed using only NAND gates or only NOR gates. A manufacturer of integrated circuits can lay down a pattern of one type of gate, and then implement any digital logic function by modifying how the gates are connected.

Digital Logic Symbols

We generally don't draw individual transistors in diagramming digital logic circuits. Instead we use abstraction to suppress unnecessary detail and represent only the required information. We need to show three things about each digital logic gate: the function of the gate, the inputs, and the output. The internal construction of the gate and certain connections are suppressed.

 

Figure 6. Digital Logic Symbols. A. NOT, B.NAND and C. NOR gates.

Figure 6 shows the symbols for the three digital logic gates we have studied in this Web Lecture. The function of each gate is represented by the shape of the symbol. These symbols are variations of the basic digital logic shapes. The triangle represents an amplifier. Adding a circle at the output makes it a NOT gate.

The bullet shape is an AND gate; adding the circle makes it a NAND gate.

The shield shape is an OR gate; with a circle it becomes a NOR gate.

The inputs are shown as wires at the left of each gate, and the output is a wire on the right. Real gates require connections to V_cc and ground in addition to their inputs and outputs. These connections are not shown on digital logic symbols, but are assumed to be present. This is another example of abstraction.

The circle at the output end of each gate is called an inversion bubble. It indicates that the output is inverted. Table 1 is the truth table for a NAND gate; each bit of the output is the complement, or inverse of the corresponding bit for the AND function. Similarly, the truth table for NOR shown in Table 2 is the inverse of theOR function.

We have examined the way three types of digital logic gates are constructed. 

Resistor Transistor Logic

       Resistor–transistor logic (RTL) is a class of digital circuits built using resistors as the input network and bipolar junction transistors (BJTs) as switching devices. RTL is the earliest class of transistorized digital logic circuit used; other classes include diode–transistor logic (DTL) and transistor–transistor logic (TTL).

Schematic of basic two-input RTL NOR gate

Advantages:

       The primary advantage of RTL technology was that it involved a minimum number of transistors, which was an important consideration before integrated circuit technology (that is, in circuits using discrete components), as transistors were the most expensive component to produce. Early IC logic production (such as Fairchild's in 1961) used the same approach briefly, but quickly transitioned to higher-performance circuits such as diode–transistor logic and then transistor–transistor logic (starting 1963 at Sylvania), since diodes and transistors were no more expensive than resistors in the IC.

Limitations:
       The obvious disadvantage of RTL is its high power dissipation when the transistor is switched on (the power is dissipated mainly by the base resistors connected to logical "1" and by the collector resistor). This requires that more current be supplied to and heat be removed from RTL circuits. In contrast, TTL circuits with "totem-pole" output stage minimize both of these requirements. Lancaster says that integrated circuit RTL NOR gates (which have one transistor per input) may be constructed with "any reasonable number" of logic inputs, and gives an example of an 8-input NOR gate. A standard integrated circuit RTL NOR gate can drive up to 3 other similar gates. Alternatively, it has enough output to drive up to 2 standard integrated circuit RTL "buffers", each of which can drive up to 25 other standard RTL NOR gates.

First benchers And Last benchers

I know there are both first benchers and last benchers reading this blog. Then where comes the difference? 

I got the idea of writing on this issue from a private channel  which aired a program on this issue called “Neeya? Naana?” meaning “You? or Me?” in . It had people from both front and bench and back bench discussing on what they liked and not. Was happy to hear that gals liked boys from back benches than from front bench. 

While front bench students believed strongly that a classroom is meant only to study back bench students argued that there is more in life than just study study and study. They strongly believed that you can learn more if you enjoy more.
There were three teachers who were present in the show who were asked what kind of students they liked? One teacher said she liked people from front bench while the other two agreed that students from the back bench impressed them more. They also mentioned that the classroom is lively because of the back benchers.

The program was concluded rightly by the host by saying these lines ” While many front bench people fail to learn what life has in it to teach them a few back benchers fail in life itself”. I strongly believe that what you learn doesn’t depend on whether you are a first bencher or the last bencher. It is never true that only people from first benches would come up in life and back benchers always lag behind. Remember our own president Dr.A.P.J.Abdul Kalam was a back bencher.

So why is there a differentiation in the minds of students based on where they sit? Why does first benchers dislike the back benchers and viceversa? Students should think on this and make sure that the classrooms are meant for learning with some fun involved in it rather than developing hatred towards each other.

My wish would be to develop a classroom with only middle benchers and no back or front benchers. Front benchers should try to learn to enjoy life and learn what life has in it to teach while back benchers should try to make sure that their life is not funny for others and they should still continue to enjoy learning but should not over do the enjoying.

Now come give your comments on what you think of this issue and don’t forget to mention whether you are a front bencher or a back bencher so that i can have a study on how many front bencher or back bencher do read blogs.

What is Real Time Operating System (RTOS)- How it works?

                When we hear the word "Operating System" the first ones that come to our mind are those we experience/use in our day to day life, say, Windows XP, Linux, Ubuntu, Windows 7 for Computer systems, Android for mobiles and many more . We mainly know that operating systems are for computers. It is a fact that most of the digital electronic devices run some sort of operating systems inside. There are many operating systems developed for micro controllers too. But here it is familiar as REAL TIME OPERATING SYSTEM. The phrase 'REAL TIME' indicates that the response of the operating systems is quick. Microcontrollers don't have much space for code. Thus the operating systems have less scope to be advanced. They try to provide at least the minimum scope of threading, scheduling and monitoring of multiple tasks for small systems.

                Usually, Real Time Operating Systems are a segment or a part of the whole program that decides the next task, task priority, handles the task messages and coordinates all of the tasks. An RTOS is a complex concept. I'd like to discuss about the concept of State Machine. Here is an implementation of what you can merrily call a state machine.

while(1)

 switch(state)

{ case 1: //Code for Task 1;

 state= 2;

 case 2: //Code for Task 2;

 state= 3;

 case 3: //Code for Task 3;

 state= 4;

 case 4: //Code for Task 4;

 state=1;

}

As you can see from the code, there is a provision of changing the execution sequence. And it can be further modified and made complex. The programmer can modify and place decision making statements (Like if, if-else, switch-case) to switch the task. And the flow of execution can be logically determined.

                A Real time operating system handles some tasks or routines to be run. The kernel of the operating system assigns CPU attention to a particular task for a period of time. It also checks the task priority, arranges the massages from tasks and schedules.

The basic functionalities an RTOS are:

• Scheduler
• RTOS Services
• Synchronization and messaging

The Scheduler

Tasks, can have three states.

• Ready to run:  When task have all the resources to run, but not in running state. It's called a ready to run task. It's the state before running.
• Running  – When a task is executing. It is known as running.
• Blocked – When a task doesn't have enough resources to run, it is sent to a blocked state.

        To schedule a task, three techniques are adapted.

• Co-operative scheduling:  In this scheme, a task runs, until it completes its execution.
• Round Robin Scheduling: Each task is assigned a fixed time slot in this scheme. The task needs to complete its execution. Otherwise, the task may lose its flow, and data generated or it would have to wait for its next turn.
• Preemptive Scheduling:  This scheduling scheme includes priority dependent time allocation. Usually in programs, 256 priority level is generally used. Each task is assigned an unique priority level. While some system may support more priority levels, and multiple tasks may have same priorities.

The Kernel takes care of the task. It involves the following

• Creating a task
• Deleting a task
• Changing the priority of the task
• Changing state of the task

RTOS Services

The heart of every operating system is called 'kernel'. Tasks are relived of monitoring the hardware. It's the responsibility of the kernel to manage and allocate the resources. As tasks cannot acquire CPU attention all the time, the kernel must also provide some more services. These includes,

• Interrupt handling services
• Time services
• Device management services
• Memory management services
• Input-output services

Messaging

Messaging provides a means of communication with other system and between the tasks. The messaging services includes

• Semaphores
• Event flags
• Mailboxes
• Pipes
• Message queues

Semaphores are used to synchronize access to shared resources, such as common data areas. Event flags are used to synchronize the inter-task activities. Mailboxes, pipes, and message queues are used to send messages among tasks.

Attributes : Circuitstoday.com

Desktop/laptop Support Engineers

Dear Candidate


we have urgent openings for Desktop/laptop Support Engineers

Positions: 3
Location: Pune

Nature of work: work hours need to be flexible. There may be rotating shifts

 
Responsibilities:

- To provide 1st level / 2nd level support to end-users in troubleshooting and resolving of desktop PC/Server problems (Hardware, software and application) and related peripherals (Printer, scanner, PDA etc).
- To perform installation, setup, configuration, migration, upgrading and maintenance of desktop PC/Server, OS, software and related peripherals.
- To be prompt and meticulous in updating of daily incident handled nto the incident management tool.
- To be responsive and pro-active when handling of end-users' PC problem and request.
- To be highly customer focused and diligent towards providing good customer service.

Requirements:

- Degree or Diploma in IT or related disciplines.
- Min 1 year related working experience preferred.
- Possess relevant IT skill set in hardware and software troubleshooting.
- Experience in supporting Windows OS, Microsoft Office Suite, Lotus Notes, Anti-virus software etc.
- Must be customer service oriented with good inter-personal and communication skills.
- Good attitude with postive mindset in learning and ready to excel.
- Able to work independently as well as in a team.
- Candidates with leadership qualities and VIP support experiences will be shortlisted for senior position
- Candidates with A+/MCP/MCSE/CCNA/ITL will be an added advantage.
- Fresh graduates are also welcome to apply.

Please send your updated resume to movvarajesh99@gmail.com


Thanks
Rajesh

Alert

BE PREPARED: BEFORE, DURING AND AFTER AN EARTHQUAKE


During an Earthquake

If you're indoors, stay there. Get under -- and hold onto --a desk or table, or stand against an interior wall. Stay clear of exterior walls, glass, heavy furniture, fireplaces and appliances. The kitchen is a particularly dangerous spot. If you're in an office building, stay away from windows and outside walls and do not use the elevator. 


If you're outside, get into the open. Stay clear of buildings, power lines or anything else that could fall on you. 


If you're driving, move the car out of traffic and stop. Avoid parking under or on bridges or overpasses. Try to get clear of trees, light posts, signs and power lines. When you resume driving, watch out for road hazards. 


If you're in a mountainous area, beware of the potential for landslides. Likewise, if you're near the ocean, be aware that tsunamis are associated with large earthquakes. Get to high ground. 


If you're in a crowded public place, avoid panicking and do not rush for the exit. Stay low and cover your head and neck with your hands and arms.

After an Earthquake

Check for fire or fire hazards. If you smell gas, shut off the main gas valve. If there's evidence of damage to electrical wiring, shut off the power at the control box. 


If the phone is working, only use it in case of emergency. Likewise, avoid driving if possible to keep the streets clear for emergency vehicles. 


Be aware that items may fall out of cupboards or closets when the door is opened, and also that chimneys can be weakened and fall with a touch. Check for cracks and damage to the roof and foundation of your home. 


Listen to the radio for important information and instructions. Remember that aftershocks, sometimes large enough to cause damage in their own right, generally follow large quakes. 


If you leave home, leave a message telling friends and family your location

BIEAP preparing first and second year Inter 2012 results

Inter 1st year 2012 results on 18th April, BIEAP Intermediate 1st Year General Results 2012. Inter 2nd year 2012 results on 22nd April, BIEAP Intermediate second Year General Results 2012.

BIEAP secretary announced today Inter results will be announced in next ten days, the paper valuation process will complete in next four days. As per secretary announcement Junior inter results likely on 18th, Senior inter results 2012 on 22 April. Inter paper valuation started on 14th March and expecting to complete in next four days.

More than 19 lakhs 58 thousand students' appeared for the both first and second year examinations. Intrusting point this year in Inter results Eamcet ranks will announce on base of Inter general results. Intermediate exam answer scripts valuation process reached to final stage will complete in 4 days. The inter examinations started on March 2 ended on 21 March. As per schedule the Inter practical examinations were finished in February. In 2012, 111148726 Inter answer scripts will be valued; an increase of four per cent from last year, the process will be completed as per schedule.

Results of the first year Intermediate examination will be released at 11.30 a.m. on 18 April Wednesday. AP IPE 1st Year General 2011 Results will be put on several websites and both marks and grades will be made available to students. However, marks will be available only on 4 websites apart from the Interactive Voice Response System (IVRS) of the BSNL.

Intermediate Exam Results marks and grades will be available on http://examresults.ap.nic.in, www.aponline.gov.in, http://results.cgg.gov.in and www.esevaonline.com. Marks can also be obtained through IVRS by dialling the number 1255225 from any place in the State without STD code from BSNL Landlines and BSNL Mobiles. Intermediate 1st Year Results grades can be obtained from the many websites.

If Card lost ?? How to retrieve New one

Yashoda Foundation and new batch commencing intimation

 From: yashoda Foundation [mailto:yashodafoundation.hyd@gmail.com] 

Subject: Introduction of Yashoda Foundation and new batch commencing intimation

 

Dear Sir/Madam,

 

 

This is to bring to your kind notice that, Yashoda Charitable Foundation was established in 2011 as the philanthropic arm of Yashoda Hospitals, to provide structure and focus to the on going social responsibility initiatives of the company. The foundation is registered under the laws of India as a charitable organization, under the direct patronage of the Yashoda Hospitals' Board of Directors. The express mission of the Foundation is to empower communities and create opportunities for the underprivileged in areas of education, training and health.

 

 

Yashoda Foundation will ensure sustainable and inclusive growth that is both environmentally friendly and socially uplifting to all the underprivileged youth. The Foundation will provide skill up gradation/vocational training to the orphan's youth Yashoda Foundation will strive hard to deliver a model to reach maximum benefits of Employment Linked Vocational Trainings Programme to the identified orphan youth of Andhra Pradesh. The foundation's prime focus to will be to provide vocational trainings as well as employable skills to orphan youth and facilitate employment after successful completion of the training course.

 

 

 We are glad to share with you as part of Employment Linked Vocational Training programme & planning to start new batches of Vocational training course for only to the orphan youth.

 

 

 We have proposed to start two new batches offering with multiple vocational courses to the Orphan youth, the details as follows:

 

S.No	Courses	Duration	Eligibility	No of seats available	Last Date of Application
1	Nursing Aid Certification Course	1 Year	10th Pass	25	10th April 2012
2	Hospitality/ Customer Relation/Sales	4 Months	10th  Pass	25	10th April 2012
3	Security Guards	1 Month	10th  Pass/Fail	60	10th April 2012

 

Note: For all the above courses we provide 100% Placement Support

 

Hence, we request you to recommend the suitable and willing aspirants/inmates from your Orphanage Homes as per the schedule for all the courses the foundation will provided 100% Placement Support to get the suitable Employment.

 

We look forward your reference as per the schedule, the registrations will closed on 10^th April 2012 evening 5pm.

 

 

Thanks & regards,

 

 

 

 

For  YASHODA CHARITABLE FOUNDATION,

Yashoda House, Plot No: 64, Co-operative Housing Society,

Nagarjuna Hills, Panjagutta, Hyderabad-82

Ph.No.: 040-67779216, 8790112424

Job in Amazon.com

Hi team,

 

Here is an opportunity to be a part of amazon.com

 

The domain is "Customer Service".

 

People who are looking only for the Technical Field don't need to respond.

 

But Amazon Customer Service is great department to work. You don't feel you are working in "Customer Service".

 

Package would be more or equal to 1.54 L.P.A.

 

If you are skilled enough you can try for the internal transfer after getting the job. But you should be 1 year with Amazon before applying for internal transfer.

 

People who are interested send in your resumes to my email address. So that I will refer you.

 

I can assure you that you will not be bored or feel regret in future of working if you get the opportunity.

 

If you have any queries reach out to me at mchintap@amazon.com or venkatsarma88@gmail.com or 98851 789 76.

I will be online from 3PM-12AM daily except (Sta,Sun). You can knock at my end in this time for any support.

 

Regards,

Murthy C.

 

Off Campus Engineering Graduate Engagement Program - 2012!!!!!

ANZ Infotech announces graduate engagement program for 2012 pass outs. Dear All As part of our Diversity Initiatives, we are conducting an All India Graduate Engagement Program for Diversity Students as per the details below: Position: Trainee Software Engineer - 2012 pass outs Qualification: Ø BE / B. Tech / M.Tech ( Computer Science, Information Technology, Electrical & Electronics Engineering ,Electronics & Telecommunication, Electronics & Instrumentation , Mechanical etc.) Ø MCA Ø 2012 pass outs only Eligibility Criteria : Ø Graduation 60% and above Ø 10th/12th: 60% and above Ø No Gap in education Ø Willingness to work in shifts, any platform & any location Ø No Supplementary (un-cleared) subjects as on date Ø Good Communication Skills Kindly upload resumes on  http://anzinfotech.com/careersin/geptse.html It will be great if you could forward this message to any of your acquaintances who are keen in participating in this test. Please note that as per our regular hiring norms, the students clearing this test with go thru the various levels of Interviews before  being made the FTE offers. For further queries or clarification reach out to campus@anzinfotech.com Please note ,we will not solicit resumes received through emails or any channel other than the AN Infotech careers portal Regards, ANZ India GEP team