Qualcomm Engineer Interview Questions, Process, and Tips

Moore state model outputs depend only on the current state, while Mealy state model outputs depend on both current state and inputs.

• Moore model: output is a function of current state only

• Mealy model: output is a function of current state and inputs

• Moore model has a separate output function, while Mealy model combines output and state transition functions

• Example: vending machine can be modeled using Mealy model as outpu...read more

State diagram and clocked D-flipflop circuit for a 0110 sequence detector.

• The state diagram will have four states: S0, S1, S2, and S3.

• The circuit will have four D-flipflops, one for each state.

• The output of the circuit will be high when the sequence 0110 is detected.

• The clock signal will be used to synchronize the flipflops.

• The state diagram and circuit can be designed using software like Quartus or Xilinx.

Parity is a method of error detection in digital communication. It involves adding an extra bit to a data stream to ensure even or odd number of 1s.

• Parity is used to detect errors in data transmission.

• It involves adding a parity bit to a data stream.

• The parity bit is set to 1 or 0 depending on whether the number of 1s in the data stream is even or odd.

• If an error occurs during transmission, the parity bit will be incor...read more

Designing a memory organization based on size and block units.

• Determine the size of the memory and the size of each block unit

• Choose a suitable memory organization scheme such as direct mapping, associative mapping, or set-associative mapping

• Implement the chosen scheme and test for efficiency and accuracy

A random number generator circuit diagram can be created using a noise source and an amplifier.

• Use a noise source such as a Zener diode or a reverse-biased transistor

• Amplify the noise signal using an amplifier circuit

• Use a comparator to convert the analog signal to a digital signal

• Add a clock circuit to control the output frequency

A Schmitt trigger/inverter is a circuit that converts a noisy input signal into a clean digital output signal.

• It has two threshold voltage levels: a high threshold and a low threshold

• The output of the circuit changes state only when the input voltage crosses one of the threshold levels

• It is commonly used in digital circuits to clean up noisy signals and to provide hysteresis

• Examples include debouncing switches, signal

To optimize power usage/delay in AND gates, arrange inputs based on their capacitance and resistance.

• Arrange inputs with lower capacitance and resistance closer to the gate

• Inputs with higher capacitance and resistance should be placed farther away

• Consider the layout of the circuit and the routing of the wires

• Simulation tools can be used to determine optimal input arrangement

Answering a question on drawing CMOS circuit and W/L sizing for a given logic equation.

• Understand the logic equation and its truth table

• Use CMOS inverter and NAND gates to implement the logic

• Size the transistors based on their role in the circuit

• Check the circuit for correct functionality

• Examples: AND gate, OR gate, XOR gate

A circuit for a set of logic equations using PLA

• PLA stands for Programmable Logic Array

• PLA is a type of digital circuit used to implement combinational logic circuits

• The circuit consists of an AND array and an OR array

• Inputs are fed into the AND array and the outputs are fed into the OR array

• Example: A PLA circuit for a 2-input XOR gate would have 2 inputs, 2 AND gates, and 1 OR gate

An SRAM cell is a type of memory cell that stores a single bit of data using two cross-coupled inverters.

• Consists of two inverters connected in a feedback loop

• Has two stable states, representing 0 and 1

• Uses two access transistors to read and write data

• Commonly used in cache memory and microprocessors

Draw output waveforms for a logic circuit given delays for gates and wires.

• Identify the logic gates and their delays

• Determine the propagation delay for each wire

• Use the delays to calculate the output waveform

• Draw the waveform using a timing diagram

Min-Cut placement algorithm is used to place blocks on a given chip area.

• Min-Cut algorithm partitions the chip into two parts and minimizes the cut between them

• It is a graph-based algorithm that uses a flow network to represent the chip and its blocks

• The algorithm iteratively partitions the network until all blocks are placed

• Example: Placing logic gates on a microprocessor chip

Design a circuit to get an output of frequency f/3 from a clock waveform of frequency f.

• Use a counter to divide the frequency by 3

• Implement a flip-flop to toggle the output

• Use logic gates to control the counter and flip-flop

My M.Tech. project was focused on developing a machine learning algorithm for predicting stock prices.

• Used historical stock data to train the algorithm

• Implemented various machine learning techniques such as regression and neural networks

• Achieved an accuracy of 80% in predicting stock prices

• Explored the impact of news articles on stock prices

Qualcomm is a multinational semiconductor and telecommunications equipment company.

• Founded in 1985 in San Diego, California

• Specializes in designing and manufacturing wireless telecommunications products and services

• Known for their Snapdragon processors used in smartphones and other mobile devices

• Also involved in developing 5G technology and Internet of Things (IoT) devices

• Has partnerships with various companies includi

Yes, I have worked in groups on various projects.

• I have worked in groups during my college projects.

• I have also worked in groups in my previous job on a software development project.

• In both cases, we had to collaborate and divide tasks among team members.

• We had regular meetings to discuss progress and address any issues.

• I found that working in a group allowed us to leverage each other's strengths and produce better res