Choose the current
10–20 mA for a bright indicator, a few mA for a panel light.
Build a basic LED (5 mm) circuit with labeled pins, component values and connection guidance.
Supply, series resistor, LED and the return to ground.
Follow the component values and pin connections
10–20 mA for a bright indicator, a few mA for a panel light.
R = (5 V − Vf) / I; take the next E24 value above.
Long lead to the resistor side, short lead and flat to ground.