Arduino Pin Current: Why the Datasheet Says 40 mA but You Should Not Use It
Series navigation: Episode 1: The Roadmap · Episode 2: Digital Multimeter and LED Circuit · Episode 3: Voltage Divider Under Load · Episode 4: What an Oscilloscope Shows · Episode 5: How Arduino Reads Sensor Voltage · Episode 6: Why Arduino Cannot Drive a Motor Directly · Episode 7 The surprising part: The ATmega328P data sheet contains a 40 mA-per-pin number, but designing an Arduino output to operate at 40 mA is the wrong conclusion. What you will learn: How to tell a damage boundary from a usable operating specification and turn one design question into a short path through a long data sheet. What you will be able to do: Identify the exact device and package, read conditions and footnotes, and record a defensible design decision instead of copying the first number you find. AI-generated illustration of a data-sheet-reading workflow. The tables are visual placeholders, not copied specifications; use the manufacturer's current document for design values. Reader...