
For a list of parts and tools that I use in this course please see https://techexplorations.com/parts/befam-parts/
Discover the basics of voltage, current, and resistance, and see how moving charges in copper wires drive work in motors and CPUs, while exploring conventional versus electron flow.
Define voltage as the force moving charged particles in a wire. Explain how a battery's electromotive force drives current and how higher voltages increase current and heat.
Explore Ohm's law and how voltage, current, and resistance relate, then calculate power and energy in simple circuits, paving the way to Kirchhoff's law in the next lesson.
Plot energy consumption in the simulator using a DC sweep with a time parameter, showing energy in joules for a 9-volt source and 1 kΩ resistor, with CSV export.
Explore Kirchhoff's law and its voltage and current forms, applying KVL and KCL to analyze series resistors, voltage drops, and conservation of energy in circuits.
Explore a simple resistor circuit using an led, a fixed resistor, and a photoresistor, then measure voltage, current, and power with a multimeter.
Simulate a simple resistor circuit in circuit lab using a photoresistor and resistor to drive an LED, perform a dc sweep, and plot voltage, current, resistance, and power as light intensity varies.
Explore resistor power ratings and how to compute power using I squared R. See practical Arduino examples with a 1 kΩ, 3.5 mA circuit and typical 1/8–1/4 W components.
Explore how a potentiometer acts as a variable resistor in a voltage divider to control led brightness, with current, voltage, and power calculated via Kirchhoff's laws.
Plot the voltage divider response to determine r2 for a 3.3 V output using a 9 V source and a 500 ohm resistor, via a dc sweep.
Learn to design a 5-V voltage divider that feeds a 3.3-V, 10-mA load, applying the 10% bleeder current rule to compute R2, R1, and related power.
Learn to calculate a voltage divider with load current using a simulator and DC sweep to pick R2 around 470 ohms for 3.3 V at 10 mA from 5 V.
Learn how pull-up and pull-down resistors create definite high or low signals for sensors and buttons connected to microcontrollers, preventing floating inputs and ensuring reliable digital readings.
Explore capacitors for microcontrollers, learning energy storage and filtering, reading values from packages or multimeters, and understanding voltage ratings across electrolytic, ceramic, and aluminum types.
Explore how a capacitor stores energy and powers an LED in a charge–discharge circuit simulated for Arduino makers. Use voltage plots and timer switches to visualize charging and discharging dynamics.
Learn to connect capacitors in parallel and in series, calculate total capacitance, determine stored charge and energy, and compare the voltage tolerance of each configuration.
Explore the RC time constant by charging and discharging a 470 microfarad capacitor through a 1 kilo ohm resistor, using an oscilloscope and multimeter, verifying a 0.47 s time constant.
Use the simulator to plot the capacitor voltage of a 7-volt RC circuit and estimate the time constant, about 481 milliseconds, when the voltage reaches 63.2% of its final value.
Explore diode fundamentals for Arduino projects, including rectifier and zener diodes, forward and reverse bias, and practical voltage regulation.
Explore how forward and reverse biasing affect diode conduction, showing how voltage threshold and current regulation work with a rectifier diode, LED, and a 240-ohm resistor, and preview zener regulation.
Explore how a pn junction diode drops voltage and behaves in forward and reverse bias using a resistor and led, demonstrated with a dc sweep simulation.
Learn how to use a multimeter to measure forward bias voltage drops for common diodes, including LEDs, rectifiers, and zeners, and compare their voltages to size current-limiting resistors.
Explore a voltage dropper circuit with three rectifier diodes and a 220 ohm resistor, showing a relatively steady output as supply varies from 3 to 7 volts.
Explore zener diodes for voltage regulation in Arduino circuits, testing reverse-bias breakdown to produce stable 3.3-volt references from a 5-volt supply using a 220-ohm resistor and a BZX55 series diode.
Explore bipolar transistors, especially NPN types, and learn to use them as switches to drive motors and high powered LEDs with examples of 2N2222 and TIP122.
calculate emitter, base, and collector currents in a npn transistor circuit using vbe ≈ 0.6 v and determine collector voltage with 12 v, 4.7 kΩ, 3.3 kΩ, and hfe.
Simulate a 2n2222 transistor circuit to observe base, emitter, and collector currents with voltmeters and ammeters, and show how base voltage controls emitter current, acting as an amplifier.
Learn how to safely drive a motor with a TIP122 transistor and a flyback diode. Control back currents from coils and protect the circuit while switching motors and relays.
Explore how fixed and adjustable voltage regulators power Arduino projects, using LM7805, LM317, and AMS1117CD, with regulator circuits built from resistors, capacitors, and voltage dividers.
Explore how a variable voltage regulator using an LM317 controls output voltage with a potentiometer and resistor divider, reduces noise with capacitors, and guides resistor calculations for a desired voltage.
Learn to calculate resistor values for the LM317 variable voltage regulator using the Vout = 1.25 × (1 + R2/R1) formula to achieve outputs such as 5 volts or 3.3 volts. Choose R1 values like 220 ohms or 1 k ohm and solve for R2 (for example 660 ohms for 5 volts and 1.64 k ohms for 3.3 volts), noting that this approach is not much harder than using a fixed regulator and that this is the final lecture leading to the course conclusion.
Simulate the LM317 adjustable regulator to study how the adjust pin and resistor divider set the output, sweeping a variable resistor to visit 0–13.5 V and regulator power.
I have updated this course with new lectures to teach you how to use an online circuit simulator. With this simulator, you can boost your understanding and learning of electronics. You will be able to conduct many experiments to examine multiple circuit scenarios and easily plot currents, voltages, and power without hardware expense. You will learn to use multiple power sources and built-in and custom component models. You can even conduct experiments that would be too dangerous to do in real life.
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Are you an Arduino maker? Can you make things by following how-to guides and are confident with writing or modifying sketches? Yet you are not so confident about things like calculating transistor currents, voltage drops, and using capacitors as filters?
You are not alone. I have been teaching Arduino and Raspberry Pi topics for years. During this time, I realized that while these platforms are great for helping you start tinkering with electronics, you will not be able to enjoy their power until you truly understand basic electronics.
This course is about helping you achieve a better understanding of the basic electronics principles and components commonly used in making platforms like Arduino and Raspberry Pi.
I have designed this course for anyone with a basic understanding of electronics who has already spent time tinkering with Arduinos.
By the end of this course, you will have learned how to use commonly used components found in Arduino projects. You will also have learned how to do the relevant measurements and calculations to help you select appropriate components for your projects.
To complete this course, you will need a few cheap and common components and tools: resistors, capacitors, transistors, LEDs, diodes, and batteries. You will also need a multimeter, a small breadboard, and jumper wires. All of these are probably things that you already have.