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Electronics

From first-principles circuits to an ESP32 capstone — then an applied Hardware Bring-Up, Instrumentation & Validation track that takes a board from bare PCB to a measured, debugged, validated system. 49 lessons, learn by doing.

Glossary → People → Review →

Foundations

Phase 0

The Promise + Safety

  1. 🗺️ #0 Course Map What You'll Build
  2. ⚠️ #1 Safety & Tools ESD, LiPo Hazards, Multimeter Basics
Phase 1

DC Circuits

  1. ⚡ #2 Ohm's Law + Power V = I × R, P = V × I
  2. 🔗 #3 Series/Parallel + Voltage Divider Resistor Combinations
  3. 🌍 #4 Ground, References, and Measurement Gotchas Why 'Ground' Is Not Magic
Phase 2

Components

  1. 🔋 #5 Capacitors + RC Time Constant Charging, Filtering, Timing
  2. 💡 #6 Diodes + LEDs Current Limiting, Polarity, Brightness
  3. 🔀 #7 Transistors/MOSFETs as Switches Why GPIO Can't Drive Everything
Phase 3

Microcontrollers

  1. 🔘 #8 GPIO Inputs Floating, Pull-ups, Debouncing
  2. 📶 #9 Timers + PWM LEDC: Duty, Frequency, Resolution
  3. 📊 #10 ADC Reading Quantization, Noise, Averaging
  4. 🔗 #11 I²C Communication Addressing, ACK/NAK, Clock Stretching
  5. 📡 #12 UART Logging + Debugging Serial Communication Workflow
  6. ⚡ #13 5V vs 3.3V Logic + Level Shifting ESP32 Rules of Engagement
Phase 4

ESP32 Deep Dive

  1. 📌 #14 ESP32 Pins: Strapping Pins, Input-Only, Boot Traps Pin Configuration Gotchas
  2. 😴 #15 Deep Sleep: Wake Sources, State, RTC Memory Power Optimization
Phase 5

Capstone

  1. 🌡️ #16 Sensor Selection + I²C Wiring SHT31/BME280 Integration
  2. 🏗️ #17 Firmware Architecture Task Loop, State Machine, Error Budget
  3. 📶 #18 Wi‑Fi Transmit Strategy Batching, Retries, Timeouts, Security
  4. 🔋 #19 Power Budget + Measurement Calculating Battery Lifetime
  5. 🚀 #20 Validation + Enclosure + Ship It Final Checklist

Applied Systems

A continuous robot-hand subsystem is the throughline: bring it up, probe it, talk to it over CAN / SPI / I²C, spin its motors, feed it clean power, and validate it to quantitative targets. Each lesson links back to the foundations it builds on.

Module 1

Bring-Up & First Power

Assessment →
  1. 🔬 #21 The Bring-Up Mindset Guilty Until Proven Innocent: Pre-Power Inspection
  2. 💨 #22 The Smoke Test Current-Limited Power-On & Fault Localization
  3. 🩺 #23 Rails, Clocks & Reset Verifying the First Layer of Life
  4. 🫀 #24 Bus & Peripheral Bring-Up JTAG to Heartbeat to One Bus at a Time
Module 2

Measurement & Instrumentation

Assessment →
  1. 🔌 #25 Probes & Grounding Why Your Ground Lead Is Lying to You
  2. ➖ #26 Differential Measurement & CMRR Reading the Difference, Rejecting the Noise
  3. 🔋 #27 Current, Power & the Art of Sensing Shunts, Hall Probes, Rogowski & Power Analyzers
  4. 🌡️ #28 Thermal & Data Acquisition Emissivity, Sensors & Logging the Whole Story
Module 3

Differential Buses · CAN & Ethernet

Assessment →
  1. 🚌 #29 CAN Physical Layer & Termination Dominant, Recessive, and the 60-Ohm Health Check
  2. 🚧 #30 CAN Errors & Debug TEC, REC, Bus-Off and the Lonely Node
  3. 🌐 #31 Ethernet PHY, Magnetics & Auto-Negotiation Why a Link Light Is Not Good Data
  4. 👁️ #32 Ethernet Debug & Signal Integrity TDR, Eye Diagrams and the PHY Registers
Module 4

Single-Ended Buses · SPI & I²C

Assessment →
  1. 🔗 #33 SPI & Its Four Modes CPOL, CPHA, CS Framing and Clock Integrity
  2. ⬆️ #34 I²C Open-Drain & Pull-Up Sizing The Rise-Time vs Sink-Current Tug of War
  3. 🔁 #35 I²C Transactions, Stretching & Recovery The 9th Clock, the Held Line, and the Stuck Bus
  4. 🧰 #36 Protocol Decode & Tooling Logic Analyzer vs Scope, and When to Reach for Each
Module 5

Motors, Actuators & FOC

Assessment →
  1. 🧵 #37 Phase Resistance & the 4-Wire Method Measuring Milliohms Without Lying to Yourself
  2. 🔺 #38 Wye, Delta & the Copper Thermometer Line-to-Line vs Phase, and Why R Tells Temperature
  3. 🧲 #39 Inductance, Ke, Kt & Pole-Pairs The Constants That Tie Volts to Torque
  4. 🎛️ #40 FOC, Current Sensing & Thermals Riding the Rotor so AC Looks Like DC
Module 6

Power Delivery & Grounding

Assessment →
  1. 🌲 #41 The Power Tree & Choosing a Regulator LDO vs Buck: Heat, Noise and Efficiency
  2. 🔌 #42 Decoupling & the Power Distribution Network A Local Battery for Every Fast Current Spike
  3. ⏱️ #43 Sequencing & Inrush The Order Rails Wake Up, and Taming the First Gulp
  4. 🪨 #44 Grounding, Return Paths & EMI Two Roads Home Is One Road Too Many
Module 7

Validation, Reliability & Test

Assessment →
  1. 📐 #45 Characterization, Verification & Validation Three Words People Use Interchangeably and Should Not
  2. 🛁 #46 Reliability: HALT, Arrhenius, Weibull & the Bathtub Breaking It on Purpose to Learn Where It Breaks
  3. 🐟 #47 Root Cause & FMEA Five Whys, Fishbones, and the Number That Ranks Risk
  4. 🏭 #48 HIL Automation & Manufacturing Test From a Bench of One to a Line of Thousands