Electrical engineer
Design the circuits, power systems and electronics that everything else is built on.
What it is day to day
- Design circuits from a requirement: choose parts, calculate values and draw the schematic.
- Simulate a design before building it, then test the prototype and compare the two.
- Lay out or review printed circuit boards, and work with manufacturing on making them reliably.
- Write test plans and reports, and review other engineers' designs.
- Specialties include power, electronics, controls, signal processing, RF and power systems for utilities and buildings.
The courses, in order
Each course builds on the one before. Every lesson runs in your browser, free, with nothing to install.
- Step 1
Electronics basics
A breadboard and a few parts, with one Uno blink at the start and no processor after it. What current, voltage, time and logic really do.
- Step 2
Digital logic and memory
Build logic from individual gates, then make a bit persist, count and move through a register.
- Step 3
Transistors and op-amps for real
Intermediate, after Electronics basics: the diode curve, biasing a BJT, common-emitter gain, the MOSFET as switch and resistor, op-amp gain both ways, comparators with hysteresis and split supplies.
- Step 4
Power and batteries
Where the volts come from and how to keep them: Ohm's law on a real meter, cells in series and parallel, a regulator, a LiPo on a TP4056, a boost converter, a battery gauge, and a power bank you build yourself.
- Step 5
Sensors and measurement
Intermediate: thermistors and RTDs, strain gauges in a Wheatstone bridge, light and IR, current on a shunt and an INA219, ADC resolution and noise, and calibration, finished with a power instrument you check against Ohm's law.
- Step 6
Relays, contactors and motor control
Intermediate, the electrician's course: relay coils and flyback diodes, latching start/stop circuits, interlocks, three-way switching, timers and ladder logic, all at low voltage, finished with a start/stop station and an emergency stop you wire yourself.
- Step 7
Read datasheets and schematics
The skill every hardware job asks for: schematic symbols, a first page, absolute maximum ratings, timing diagrams, register maps and pinouts, each checked on real parts. Ends with a sensor brought up from its datasheet alone.
- Step 8
AC, signals and filters
Advanced, after Transistors and op-amps for real: sine, peak and RMS, reading a scope, RC and RL filters, frequency response, RLC resonance and active filters.
- Step 9
From gates to a computer
Start with one NAND gate, package every circuit you build into a chip, and use your chips to build the next one: an adder, memory, a CPU of your own, and a computer that runs your program.
- Step 10
Breadboard to PCB
Take three working circuits from the breadboard to a finished board: the schematic, footprints, placement, routing, design rules, and what a board house needs.
- Step 11
Power electronics
Advanced: switches, inductors and heat: buck and boost converters from loose parts, PWM, MOSFET drivers, H bridges, efficiency, and a regulated supply you set from its formula.
- Step 12
Circuit design capstone
Expert: take one product from a written requirement to a tested board: blocks, a schematic worked out on paper, part choice, simulating the corners, PCB layout, a test plan, and a revision that fixes what the tests found.
- Step 13
Portfolio and interviews
Turn finished projects into a job search: choose and document portfolio pieces, share links that run, read job posts and answer technical questions out loud.
Your skills checklist
- Circuit laws, dividers and measurementElectronics basics
- Combinational and sequential logicDigital logic and memory
- Transistor and op-amp circuits, designed and measuredTransistors and op-amps for real
- Power supplies, regulators and batteriesPower and batteries
- Reading and writing datasheets and schematicsRead datasheets and schematics
- AC analysis, frequency response and filtersAC, signals and filters
- How a computer is built from gatesFrom gates to a computer
- PCB layout from a working breadboardBreadboard to PCB
- Switching converters and power stagesPower electronics
- A complete design from requirement to testCircuit design capstone
Projects to build and show
Open one, run it, change it, then share your version as a link that runs. The last course in this guide shows how to write each one up.
After Mokxi, in the real world
Mokxi teaches the skills; employers, schools and licensing boards set their own rules. These are the common routes, and they vary by place.
Training and education
- Electrical engineering jobs usually ask for a bachelor's degree in electrical engineering or a close field. In the US, programs accredited by ABET are the usual standard.
- Many students start at a community college and transfer to a four-year program. Check transfer agreements early so your math and science credits count.
- Internships and co-ops during the degree are one of the strongest things on an engineering resume.
Certifications
- Most electronics design jobs do not require a license. Projects, internships and the degree carry the weight.
- Some engineers take the Fundamentals of Engineering (FE) exam near graduation as a first step toward a professional license.
Licensing
- A Professional Engineer (PE) license is needed in some roles, most often power systems, utilities and building design, where an engineer signs off on work for the public.
- In the US the usual path is an accredited degree, the FE exam, several years of supervised work and then the PE exam. Exact rules vary by state, and other countries have their own systems.
Entry-level titles to search
- Junior electrical engineer
- Electrical engineer I
- Hardware engineer (entry level)
- Electronics design engineer
- Test engineer
- Electrical engineering intern
Questions you may be asked
Short answers drawn from the courses. Say each one out loud, then check it on a circuit.
Design an LED circuit for a 5 V supply.
Pick a current, say 10 mA, and the LED's forward voltage, say 2 V. R = (5 - 2) / 0.01 = 300 ohm, so use the next standard value up and check the resistor's power: about 30 mW.
What is the gain of an inverting op-amp amplifier?
Minus Rf over Rin. 10 k over 1 k gives a gain of -10: ten times bigger and upside down.
What is the corner frequency of an RC low pass?
f = 1 / (2 x pi x R x C). At that frequency the output is down about 3 dB, roughly 70 percent of the input.
Linear regulator or switching regulator?
A linear regulator is simple and quiet but burns the voltage difference as heat. A switching regulator is efficient over big differences but noisier and more complex. Choose by power, heat and noise.
What does a decoupling capacitor do?
Placed right at a chip's power pins, it supplies the fast bursts of current the chip draws, keeping its supply steady and noise off the rail.
How does a transistor work as a switch?
A small base current (or gate voltage for a MOSFET) turns it fully on so a much larger current flows from collector to emitter. Size the base drive for the load current.
What is the difference between a latch and a flip-flop?
A latch follows its input while enabled. A flip-flop only captures its input on a clock edge, which keeps synchronous logic predictable.
How would you test a new board?
Inspect it, check for shorts on the rails with power off, power up with a current-limited supply, check every rail, then bring up each function one at a time against a test plan.
Tell me about a design trade-off you made.
Name the requirement, the two options, what each cost (parts, power, heat, time) and why you chose one. Say what you would change with hindsight.
Step 1 is Electronics basics
A breadboard and a few parts, with one Uno blink at the start and no processor after it. What current, voltage, time and logic really do.