Syllabus for Top-Tier EE/Robotics Internships

A set of flashcards based on key concepts from the Electrical Engineering and Robotics syllabus, covering critical insights for internships.

What is the volatile keyword in C, and why is it critical in embedded systems?

The volatile keyword is a type qualifier that tells the compiler that a variable's value can be changed by something outside the normal flow of the program (e.g., hardware, interrupts, or another thread). It prevents the compiler from optimizing away reads or writes to that variable.

Differentiate between the Stack and Heap in an embedded system's memory.

The Stack is used for local variables, function call information, and operates on a LIFO principle with automatic memory management. The Heap is for dynamic allocation, where memory is explicitly requested and freed by the programmer during runtime.

What are the best practices for writing an Interrupt Service Routine (ISR) in embedded C?

Keep ISRs short and fast, avoid complex calculations and blocking calls, perform only critical tasks, use volatile for shared variables, clear interrupt flags promptly, and defer non-critical work.

What is priority inversion?

Priority inversion occurs when a high-priority task is blocked by a lower-priority task that holds a shared resource, leading to unpredictable delays in executing the high-priority task.

Explain the fundamental differences between UART, SPI, I2C, and CAN.

UART is asynchronous and point-to-point, SPI is synchronous and full-duplex, I2C is synchronous and multi-master/slave, and CAN is asynchronous and multi-master with broadcast capability.

What are differential pairs, and why is impedance matching crucial for signal integrity in high-speed PCB design?

Differential pairs are closely routed traces carrying equal and opposite signals, making them immune to common-mode noise. Impedance matching prevents signal reflections that can distort data.

What is the purpose of decoupling capacitors in power integrity?

Decoupling capacitors act as local, low-impedance energy reservoirs for ICs, supplying transient current demands and filtering high-frequency noise from the power supply.

Explain the operation of a synchronous buck converter in continuous conduction mode (CCM).

In a synchronous buck converter, when the high-side switch is ON, energy is stored in the inductor. When it is OFF, energy is discharged through the load, and the output voltage is determined by the duty cycle.

What are the key parameters to consider when selecting a power MOSFET for a switching application?

Key parameters include RDS(on) for conduction losses, Gate Charge (Qg) for switching losses, Breakdown Voltage (Vds), Maximum Current (Id), and Thermal Resistance (Rth).

What is the role of the Proportional (P), Integral (I), and Derivative (D) terms in a PID controller?

P responds to current error, I to accumulated past error, and D to the rate of change of error; tuning involves balancing these terms for desired system response.

What is a Kalman Filter, and why is it used in robotics?

A Kalman Filter is an optimal estimation algorithm that uses a series of noisy measurements to produce more precise estimates of unknown variables.

State the two 'golden rules' of ideal op-amps and explain their significance.

Golden Rule 1 (Virtual Short): V- = V+. Golden Rule 2 (No Current into Inputs): I- = I+ = 0. These rules simplify analysis of op-amp circuits based on their ideal characteristics.

Explain the concept of resonance in a series RLC circuit.

Resonance occurs when inductive reactance equals capacitive reactance, maximizing current. The resonant frequency can be calculated as f = 1/(2π√(LC)).

Compare and contrast Bipolar Junction Transistors (BJTs) and Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs).

BJTs are current-controlled devices suitable for low-to-medium power applications, while MOSFETs are voltage-controlled, favored for high-power and high-speed switching due to lower on-resistance.