The curriculum · sunbench

1Foundations, direct current

1.1
Charge and its movement the crossroads →
What charge is, who carries it in each medium, and why it resists: the step before the quantities.
My targets
1. Explain electric charge (positive, negative, the coulomb), the atom, and why metals have free electrons.
2. Name the charge carriers by medium: electrons in a metal, ions in an electrolyte (the cell, the pack, salt water), electrons and holes in a semiconductor, ions and electrons in an arc or a plasma, and say which way each one goes.
3. Explain conventional current and electron flow, and why the two conventions coexist without disturbing the calculations.
4. Explain conduction and resistance at the level of atoms: collisions, thermal agitation, why a metal’s resistance rises with temperature and a semiconductor’s falls.
5. Explain what happens inside a cell: the reaction that separates the charges, the ions crossing the electrolyte, the electrons going round through the circuit, a battery is a current of ions inside.
6. Distinguish conductor, semiconductor and insulator by what they offer to charges (free electrons, band gap), and say why copper, aluminum and the nickel of pack strips don’t conduct alike.
7. Diagnosis: a contact that heats up, or a cell that no longer delivers in the cold, say which movement of charges is hindered, and where.
1.2
The quantities the crossroads →
Charge, current, voltage, resistance, power, energy; units, prefixes, orders of magnitude.
My targets
1. Name the six quantities (charge, current, voltage, resistance, power, energy), their unit and their symbol, unaided.
2. Explain the difference between power and energy with a tool battery: the Wh on the label, the W of the motor, how long it lasts.
3. Convert between prefixes (mA ↔ A, kΩ ↔ Ω, mAh ↔ Ah ↔ Wh at a given voltage) without error.
4. Give the order of magnitude of an LED, a Raspberry Pi, an EGO chainsaw and a 100 W panel, in current and in power.
5. Diagnosis: a "5 Ah" pack that doesn’t last the advertised time, say which quantities to measure to decide between pack and tool.
1.3
Ohm’s law and power the crossroads →
Calculate, predict heating.
My targets
1. Calculate the third quantity from two (V, I, R) without a table.
2. Predict the dissipated power and choose a resistor of sufficient rating, with a working margin.
3. Measure V and I on a real circuit and recover R within 5 %.
4. Explain why a wire that’s too thin heats up, with the calculation, and choose a wire gauge for a given current.
5. Read a wire gauge table (AWG) and calculate the voltage drop over ten metres of cable for a given current.
6. Diagnosis: a burnt resistor on a board, say why from the schematic, and what it protected.
1.4
Series, parallel, mixed the crossroads →
Voltage and current dividers.
My targets
1. Calculate the equivalent resistance of a series, parallel and mixed circuit, then verify it with the ohmmeter.
2. Size a voltage divider to read a 48 V battery on a 3.3 V input, and say what the downstream load does to it.
3. Explain why a pack’s cells are in series for voltage and in parallel for capacity, with the numbers of a real pack (e.g. 10S3P).
4. Predict the current in each branch of a parallel of unequal resistors, then measure it.
5. Build a Wheatstone bridge, balance it, and explain why it’s the basis of most strain-gauge sensors.
6. Diagnosis: an LED string with half the lights out, deduce the wiring and locate the break without taking it apart.
1.5
Kirchhoff and network analysis the crossroads →
Loops, nodes, Thévenin, superposition.
My targets
1. State Kirchhoff’s two laws and apply them to a two-loop circuit.
2. Solve a network by loops or nodes, and verify the result with the multimeter on the circuit.
3. Replace a real source by its Thévenin equivalent, and use it to predict the voltage under load.
4. Say when superposition applies and when it doesn’t (a circuit with a diode).
5. Go from a Thévenin equivalent to a Norton equivalent and say when each simplifies the calculation.
6. Diagnosis: a measured voltage that doesn’t match the calculation, find the contact resistance or the forgotten ground path.
1.6
Passive components the crossroads →
Resistors, capacitors, inductors; codes, tolerances, dissipated power, what kills them.
My targets
1. Read a resistor’s value from the colour code and SMD marking, then verify it.
2. Choose a capacitor by capacitance, voltage and type (ceramic, electrolytic, film), and say which doesn’t belong where.
3. Explain what an inductor does to a changing current, and why a flyback diode goes with a relay or a motor.
4. Name what kills each component: overvoltage, overheating, polarity, the age of an electrolytic.
5. Measure a capacitor and an inductor with the right instrument and compare to the marking.
6. Recognize and measure the variable components: potentiometer, thermistor (NTC, the one in packs), photoresistor, varistor; say what each makes vary.
7. Diagnosis: a bulging electrolytic on a power supply, say what it was doing there, what its failure causes, and how to replace it (value, voltage, polarity).
1.7
Transients the crossroads →
RC, RL, time constants.
My targets
1. Calculate the time constant of an RC and an RL and say what it means (63 %, five time constants).
2. Plot a capacitor charging on the oscilloscope and recover RC.
3. Explain why a button bounces and how an RC filters it.
4. Size an RC for a given delay, build it and measure it.
5. Explain why a capacitor blocks DC and passes change, and use it to couple two stages.
6. Diagnosis: a circuit that starts "too fast" or "too late", find the time constant at fault.
1.8
Magnetism and electromagnetism the crossroads →
Relays, solenoids, the brushed motor as a first motor.
My targets
1. Explain what a current does in a coil and what a moving magnet does in a coil (the two directions of electromagnetism).
2. Drive a relay from a microcontroller with a transistor and flyback diode, and say why each is there.
3. Take apart a brushed DC motor, name its parts and explain commutation.
4. Measure the starting current of a brushed motor and explain why it exceeds the rated current.
5. State Lenz’s law, show induction with a magnet and a coil on the oscilloscope, and say that the transformer, the motor and the generator are the same thing seen three times.
6. Measure the inductance of a coil and say what the iron core changes.
7. Diagnosis: a brushed motor that runs in fits and starts, brushes, commutator or supply; say how to decide.
1.9
Sources the crossroads →
Primary cells, rechargeable cells, power supplies; internal resistance, drop under load.
My targets
1. Explain a source’s internal resistance and measure it on a cell (open-circuit voltage, voltage under a known load).
2. Predict a pack’s voltage drop under a given load, then measure it.
3. Read a power supply’s characteristics (voltage, max current, regulation) and know what it does when you exceed them.
4. Put two sources in series and in parallel, say when it’s allowed and what happens when they differ.
5. Compare primary cells and rechargeable cells (alkaline, NiMH, lead, lithium): voltage, curve, self-discharge, and choose for a given use.
6. Diagnosis: a tool that stops under load while the pack reads full, internal resistance, weak cell or BMS; the measurement path to decide.

1Foundations, direct current

Charge and its movement the crossroads →

The quantities the crossroads →

Ohm’s law and power the crossroads →

Series, parallel, mixed the crossroads →

Kirchhoff and network analysis the crossroads →

Passive components the crossroads →

Transients the crossroads →

Magnetism and electromagnetism the crossroads →

Sources the crossroads →

2Alternating current and signals

The sine wave the crossroads →

Reactance and impedance the crossroads →

Passive filters and resonance the crossroads →

Transformers and the mains the crossroads →

Non-sinusoidal signals the crossroads →

Power in AC the crossroads →

3Semiconductors and analog

Diodes the crossroads →

Bipolar transistors the crossroads →

MOSFETs the crossroads →

Operational amplifiers the crossroads →

Power supplies the crossroads →

Oscillators and timers the crossroads →

Reading a datasheet the crossroads →

Thyristors, TRIACs and isolation the crossroads →

Sensors and their conditioning the crossroads →

4Digital and microcontrollers

Logic the crossroads →

Logic circuits the crossroads →

Interfaces the crossroads →

Analog ↔ digital the crossroads →

The microcontroller the crossroads →

From microcontroller to computer the crossroads →

The minimal circuit of a bare chip the crossroads →

Programming and debugging on your own board the crossroads →

Low power the crossroads →

Designing and having a board made the crossroads →

Wireless the crossroads →

Closed-loop control, PID the crossroads →

5Instrumentation and measurement

The multimeter the crossroads →

The oscilloscope the crossroads →

Bench supply and electronic load the crossroads →

Measuring over time the crossroads →

Uncertainty the crossroads →

Building and repairing the crossroads →

6Power, panels, packs, motors, converters

The lithium cell the crossroads →

The pack the crossroads →

The charger the crossroads →

The panel the crossroads →

The motor the crossroads →

The controller the crossroads →

Converters the crossroads →

Heat the crossroads →

7Safety

Current and the body the crossroads →

Working safely at the bench the crossroads →

Lithium the crossroads →

Stored energy and the DC arc the crossroads →

8Systems, reading and designing a complete device

Reading a device schematic by blocks the crossroads →

The power supply as a system the crossroads →

The audio amplifier, stage by stage the crossroads →

The interfaces between stages the crossroads →

Feedback the crossroads →

The guitar amplifier as a project the crossroads →

The microcontroller system the crossroads →

Designing, from specification to schematic the crossroads →

Troubleshooting by stages the crossroads →

Simulation the crossroads →

Electromagnetic compatibility the crossroads →

Audio beyond the amplifier the crossroads →