Jeevashree Srinivas

Task 1- LTspice and KiCad

Objective

Design and simulate a 555 timer-based astable multivibrator using LTspice to observe frequency and pulse width behavior. Use KiCad to create a schematic of an LED blinking circuit and design a PCB layout with proper footprints and routing. This task introduces simulation and PCB design fundamentals.

Outcome

I designed and simulated 555 timer astable and obtained the square pulse

LTspice

Kicad

Task 3 - Temperature and Humidity Detection(Embedded)

Objective

Use the LM35 analog temperature sensor to monitor ambient or localized heat (e.g., near a soldering iron). When temperature exceeds a threshold, turn on an LED using a BJT as a switch. In parallel, use the DHT11 digital sensor to read and display temperature and humidity on a 16x2 LCD.

LM35

• LM35 is a precision temperature sensor.
• It gives an analog output voltage proportional to the temperature in °C.
• It is manufactured by Texas Instruments.
• It is part of the LMxx series of analog sensors
• The sensor’s output voltage changes linearly with temperature.
• It produces 10 mV for every 1°C change.
• Example: 25°C → 250 mV output
  30°C → 300 mV output

DHT11

DHT11 is a digital temperature and humidity sensor.

• It measures both temperature and relative humidity (RH).
• It provides a calibrated digital output (no need for analog-to-digital conversion).
• It is a low-cost and easy-to-use sensor, commonly used in weather stations and IoT projects.
• A capacitive humidity sensor to measure moisture in the air.
• A thermistor (temperature-sensitive resistor) to measure temperature.
• It has an 8-bit microcontroller inside to process data and send it as a digital signal.

Task 5 - Battery Capacity Measurement(Power Electronics)

Objective

Monitor the voltage of a Li-ion battery using analog input on Arduino. Use a MOSFET as a switch to disconnect the load when voltage drops below a safe threshold. Ensures safe battery operation and demonstrates basic battery protection logic.

Working Principle

• The Arduino reads the scaled battery voltage through A0.
• The code calculates the actual battery voltage using the voltage divider ratio.
• If the voltage is above the threshold (e.g., 3.0V), the MOSFET is ON, and the LED glows.
• If the voltage drops below the threshold, the MOSFET turns OFF, and the LED turns off, simulating battery protection.

Outcome

I did this task using Tinkercad. The circuit was simulated and tested successfully. Open my Tinkercad

Task 6 - Battery Charging(Power Electronics)

Objective:

To charge a Li-ion battery using a solar panel and a solar charging module.

Components Used:

• Solar panel
• Li-ion battery
• Solar charging module (TP4056 or similar)
• Connecting wires

Outcome

Through this experiment, the practical implementation of solar-based charging was understood. It demonstrates how renewable energy can be used effectively to charge batteries and power small electronic devices.

Task 8 - Simple Electric Circuits Simulation on MATLAB(Power Electronics)

Objective

Learn the basics of Simulink in MATLAB by designing a simple RLC or transistor-based circuit. Simulate voltage, current, and frequency responses over time using virtual probes and scopes.

Circuit description

The circuit consists of a resistor (R), inductor (L), and capacitor (C) connected in series to a voltage source. The RLC circuit is designed using Simulink blocks such as:

• Voltage Source (for AC input)
• Resistor, Inductor, Capacitor blocks (from Simscape Electrical library)
• Scope and Current Measurement blocks (to visualize waveforms)

Outcome

Understood how to design and simulate basic electrical circuits using MATLAB Simulink. Learned how to analyze voltage, current, and frequency responses using virtual scopes.

Task 11 - Buck Converter on LTspice (Power Electronics)

Objective

Design and simulate a DC-DC buck converter in LTspice. Observe input and output voltages, inductor current waveform, and switching frequency. Understand step-down conversion and efficiency aspects.

Outcome:

Understood the working principle of a DC-DC buck converter and how to simulate it in LTspice. Learned how switching and filtering affect output voltage and efficiency.

Task 12 - Wireless Charger Simulation on Tinkercad (Power Electronics)

Objective

Simulate inductive power transfer between a transmitter and receiver coil on Tinkercad using basic circuit blocks. Demonstrates wireless charging principles through virtual components and LED indication.

Outcome

Open my Tinkercad design

Task 4 - BLDC Motor And Hall Effect Sensor

Objective

Connect a BLDC motor with a Hall effect sensor to measure its speed. The output of the Hall sensor is read by Arduino to calculate RPM and display it via the Serial Monitor. This task demonstrates motor speed sensing and signal interpretation.

Outcome

• Hall Effect: The Hall Effect is the phenomenon where a voltage difference is generated when an electric current passes through a semiconductor placed in a magnetic field. This is used in Hall Effect sensors to detect the presence of a magnetic field.

1.The Arduino reads the digital signal from the Hall Effect sensor.
2.Each time the magnet passes the sensor, it triggers a LOW signal.
3.The Arduino counts these signals and calculates the RPM by multiplying the pulses per second by 60.
4.The calculated RPM is then displayed on the serial monitor every second.
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Task 14 - LED Brightness Control Using PWM and MOSFET (Power Electronics)

Objective

Use an Arduino and an N-channel MOSFET to control LED brightness through Pulse Width Modulation (PWM). The Arduino sends a signal to the MOSFET’s gate, allowing current flow between the drain and source. By varying the PWM duty cycle, you can control the LED’s brightness—higher duty cycle means more brightness, and lower duty cycle means dimmer output.

Outcome

• LED brightness was successfully controlled using Pulse Width Modulation (PWM)
• The duty cycle of the PWM signal determined the brightness level of the LED.
• A MOSFET was used as an electronic switch to handle higher current safely.
• PWM control allowed efficient brightness variation without changing the supply voltage.
• This experiment demonstrated the practical application of power electronics in LED lighting control.

Task 17- Building a Basic H-Bridge Motor Driver using MOSFETs (Power Electronics)

Objective

You are required to design and build a basic H-Bridge motor driver circuit using N-Channel and/or P-Channel MOSFETs. The H-Bridge should allow you to control the direction of a DC motor using digital signals (e.g., from Arduino or switches)

Outcome

In this task, a basic H-Bridge motor driver using MOSFETs was designed and implemented. The circuit successfully controlled the direction of a DC motor by switching appropriate MOSFET pairs using digital signals. This experiment helped in understanding power electronic switching, motor control principles, and safe handling of inductive loads.