需求
“A Raspberry Pi GPIO18 3.3 V output driving LED1 through a 330 Ω series resistor to ground.”
接著試試Change the resistor to 220 Ω.Add a second LED branch.
這張圖裡有什麼
看懂背後的決策。
01
Use 330Ω series resistor for ~3mA LED current from 3.3V GPIO
02
Connect LED cathode to common ground (0V)
03
Model GPIO as a 3.3V DC supply with output net
Reuse for any single-LED status indicator on Raspberry Pi or similar 3.3V logic outputs where current must be limited to safe levels.