L&T Emsys Interview Question Bank – Part 1

Let us now look at the questions asked in the recent times of interviews of L&T Emsys, a division of L&T Technology Services that deals with embedded systems and software development (and thus, the name L&T Emsys). It is an ECE core company which was incorporated in February 2001 and has three development centres in Mysore, Bangalore and Mumbai. These questions might help you prepare for on-campus and off-campus interviews of the above said company as well as those which work in similar domains. Let’s start with them…

Q : When does a UJT start conducting?

A : UJT (Uni-Junction Transistor) starts conducting when its emitter is forward biased.

Q : What is Schmitt trigger otherwise called?

A : Schmitt Trigger is also called as bi-stable multivibrator (i.e. latch or flip-flop).

Q : At which OSI layer does the retransmission of packets take place?

A : The retransmission of packets takes place in the Network layer of OSI model.

Q : Which component is the Heart of Analog to Digital converter (ADC)?

A : The heart of ADC is the comparator.

Q : How will you generate a rectangular wave?

A : There are two ways for generating a rectangular wave – using Schmitt trigger circuit, and using a DAC (Digital to Analog Converter) along with a microprocessor having software delays of appropriate time period.

Q : For differential amplifier, CMRR value should be large or low?

A : CMRR value should be preferably large for differential amplifier.

Q : What is the time constant for differentiator and integrator?

A : Time constant (=RC) for a differentiator should be small and that of integrator, should be large.

Q : Write the dual to A+1.

A : The dual to A+1 is A.0, reason being + should be changed to . and 1 to 0 (and vice-versa).

(Continued to Part 2…)

Gautam Vashisht