PAGE 025 OF 150 · COLOURS, SIZES & TYPES
3 mm LEDs
The 3 mm size is compact and common on small boards.
LED SYMBOLTriangle points from anode to cathode; the arrows show light leaving the part.
About 3 mm LEDs
The 3 mm LED has a body about three millimetres across and is common on small boards and front panels.
Typical figures
- Maximum current about 20 mA, with 5 to 15 mA used in practice
- Viewing angle commonly 30 to 60 degrees
- Legs spaced for 2.54 mm breadboards and perfboard
When to choose it
Choose 3 mm when space is tight or a discreet indicator is wanted. Panel holes of about 3.1 to 3.2 mm, or a plastic clip holder, keep it in place.
REMEMBER
Colour is set by the semiconductor material, not by the plastic lens.Try it yourself
Sketch the circuit on paper first, calculate the values, then build it on a solderless breadboard using a low-voltage supply. Measure with a multimeter before you make anything permanent.
Explore LED clocks, stopwatches and electronics at cosycom.com.