L&T Technology Services

Engineering context

LTTS provides embedded engineering services including hardware/software development, integration and product testing. Preparation should follow the customer domain and engineering role specified in the vacancy. Official company reference.

Selection process

Use the current vacancy, official hiring communication and assessment instructions. Eligibility, tests, interview count and topics vary by role, location and hiring route; this guide does not verify a fixed sequence of company interview rounds.

What to revise

Embedded C, digital interfaces, RTOS fundamentals, debugging and verification; add RTL or communications for roles requesting them.

Use the relevant subjects below as references; you do not need to revise every subject equally for every role.

• Networks & Circuits
• Signals & Systems
• Electronic Devices
• Analog Circuits
• Digital Circuits
• Control Systems
• Communications
• Electromagnetics
• Microprocessors & Embedded
• VLSI Design

Practice questions

These are original preparation questions, not a claim that the company asked them.

1. What is the difference between analog and digital signals? Analog information varies continuously in amplitude; digital information uses discrete symbols. Physical digital waveforms are still continuous-time electrical signals, and noise immunity depends on margins, coding and the receiver.

2. Explain the working principle of a microprocessor. A microprocessor is an integrated circuit that contains the functions of a central processing unit (CPU) of a computer. It performs arithmetic and logic operations, controls data flow, and manages input/output operations.

3. What are the key components of a communication system? A communication system typically includes a transmitter, a communication channel, and a receiver. The transmitter encodes the message into a signal, the channel carries the signal, and the receiver decodes it back into the message.

4. How do you design a low-pass filter? A low-pass filter allows signals with a frequency lower than a certain cutoff frequency to pass through and attenuates frequencies higher than the cutoff. It can be designed using resistors and capacitors in an RC circuit configuration.

5. What is VLSI design, and why is it important? VLSI (Very Large Scale Integration) design involves creating integrated circuits by combining thousands of transistors into a single chip. It is crucial for developing compact, efficient, and high-performance electronic devices.

6. Describe the function of an operational amplifier. An operational amplifier is a high-gain voltage amplifier with differential inputs and usually a single-ended output. It is used in various applications, including signal conditioning, filtering, and mathematical operations.

Before the interview

• Review your academic projects and be prepared to discuss your role and the technologies used.
• Highlight any relevant internships or work experience, focusing on skills gained.
• Research L&T Technology Services, including recent projects, technological focus areas, and company culture.
• Prepare questions to ask the interviewer about the role and the company.
• Practice common interview questions and conduct mock interviews to build confidence.