Embedded Systems monk fueled by coffee, coding, football, and finance. Writing software for chips by day, yelling at the TV during Man United games by night.
Sep 6 • 11 tweets • 9 min read
So, I have been harping on about electronics for a while, and it's about time that I made a list of topics that should be in your arsenal if you are looking to get into it.
An incredibly long thread -
1) Fundamentals of Electricity - You think you know this. You don’t.
1. Voltage (Potential Difference)
Voltage is the electrical “pressure” that pushes charge through a circuit, measured in volts (V). It defines how much energy per charge is available and is crucial for understanding battery ratings, logic levels, and maximum component ratings.
2. Current (Amperes)
Current is the flow of electric charge per second, measured in amperes (A). It determines heat generation, motor torque, and LED brightness, and it’s essential to size wires, traces, and protection devices correctly.
3. Resistance (Ohms)
Resistance opposes current flow and is measured in ohms (Ω). It’s used to set currents, divide voltages, and control bias in circuits. Heat dissipation due to resistance is given by P=I²R and must be managed.
4. Power (Watts)
Power is the rate of energy use, calculated as P=VI, I²R, or V²/R. It’s important when sizing components to prevent overheating, particularly for resistors, regulators, and transistors.
5. Energy (Joules)
Energy is the capacity to do work, measured in joules (J), and is calculated as E = P·t. It helps estimate battery runtime and capacitor storage, with capacitors storing energy as ½ C·V².
6. Ohm’s Law
Ohm’s Law links voltage, current, and resistance in the equation V=IR. It’s the foundation for most DC calculations, such as selecting the right resistor for an LED.
7. Series Circuits
In a series circuit, components share the same current, but their voltages add up. A break in one component stops the entire chain, making total voltage drop an important design factor.
8. Parallel Circuits
Parallel circuits have the same voltage across each branch, but the total current is the sum of branch currents. Current sharing requires care to avoid imbalance between branches.
9. Kirchhoff’s Voltage Law (KVL)
KVL states that the sum of all voltage rises and drops around a closed loop equals zero. It’s essential for verifying voltage distribution in a circuit.
10. Kirchhoff’s Current Law (KCL)
KCL states that the total current entering a node equals the total current leaving it. It’s a key principle for solving unknown currents in multi-branch circuits.
