AKTU · EE / ELCE · Semester 1
AEC101A
Ten long questions from every unit — the ones that keep coming back — plus short-answer questions covering the whole syllabus for the compulsory first question. Answers are in the complete notes for this paper.
Every unit of the AEC101A / AEC201A syllabus, written against the official scheme: Unit I Diodes and Power Supply Circuits; Unit II Transistors as Switches and Amplifiers; Unit III The Operational Amplifier; Unit IV Digital Electronics Basics; Unit V Electronic Systems and Emerging Applications. Worked examples, tables and diagrams throughout, with the high-yield points marked.
AKTU end-semester examination, 2023. Course code BEC101.
Official AKTU syllabus, effective from the academic session 2026-27 (AICTE model curriculum / NEP 2020).
Diodes and Power Supply Circuits: p-n junction — concept of depletion layer, forward and reverse bias; ideal diode vs real diode; V-I characteristics; diode as a switch; half-wave and full-wave bridge rectifier; filter capacitor; Zener diode — Zener breakdown, voltage regulator circuit; LED — working and current-limiting resistor; applications: USB charger rectifier, 5V/3.3V regulated supply for Arduino/Raspberry Pi, LED indicators in electronics products Transistors as Switches and Amplifiers: Bipolar Junction Transistor (BJT) — Construction & VI characteristics of BJT, NPN and PNP, three regions of operation (cut-off, active, saturation); BJT as a switch (digital control of relay, buzzer, motor); BJT as a common-emitter amplifier (concept and gain); Introduction to FETs, MOSFET — N-channel MOSFET, gate-source voltage, MOSFET as a switch; why MOSFET is preferred in digital ICs and power electronics; applications: transistor switch for driving a relay in home automation, MOSFET in motor speed control (PWM concept), transistor in class-A amplifier for audio Operational Amplifier (Op-Amp): Ideal op-amp characteristics — infinite gain, infinite input impedance, zero output impedance; practical characteristics of 741 IC, inverting amplifier — voltage gain formula; non-inverting amplifier — gain formula; voltage follower (buffer); summing amplifier; comparator — op-amp as comparator, threshold detection; applications: sensor signal amplification (temperature, light, pressure), audio amplifier, automatic night lamp comparator circuit, differential amplifier for ECG/EEG front-end (concept) Digital Electronics Basics: Number systems — binary, decimal, hexadecimal (conversion only); logic levels (HIGH/LOW, 0/1); basic logic gates — AND, OR, NOT, NAND, NOR, XOR with truth tables; Boolean algebra — basic laws and De Morgan's theorems; k-map (upto 4 variables), half adder and full adder (truth table and logic diagram); multiplexer concept; flip-flop — SR and D flip-flop (concept only); applications: binary addition in CPU ALU, MUX in data routing, digital signals in microcontroller I/O, basics of PLA / PLD devices. Electronic Systems and Emerging Applications: Microcontroller overview — what is a microcontroller, GPIO pins, ADC- ADC types – digital ramp type & flash type ADC, PWM (concept only, not programming); communication interfaces — UART, SPI, I2C (what they do, not detailed protocol); sensors and signal chain — sensor → conditioning (op-amp) → ADC → microcontroller; wireless communication basics — Bluetooth, Wi-Fi, Zigbee (concept); power management in electronics — LDO regulator, DC-DC converter (concept); applications: IoT weather station, smart home sensor node, wearable health device, EV battery management system (BMS) electronics overview