What is MLED(Miniature light-emitting diode)?
Miniature light-emitting diodes are mostly single-die LEDs used as indicators, and they come in various-size through-hole and surface mount packages:
- SMD
- 2 mm
- 3 mm (T1)
- 5 mm (T1¾)
- 10 mm
Other sizes are also available, but less common.
Some applications (e.g. building custom LED panels for alarm clocks, dashboards backlight solutions and alike), require use of so-called ‘unpackaged LEDs’, consisting of nothing but semiconductor chip with conductive wire attached.
Common package shapes:
- Round, dome top
- Round, flat top
- Rectangular, flat top (often seen in LED bar-graph displays)
- Triangular or square, flat top
The encapsulation may also be clear or semi opaque to improve contrast and viewing angle.
There are three main categories of miniature single die LEDs:
Low current — typically rated for 2 mA at around 2 V (approximately 4 mW consumption).
Standard — 20 mA LEDs at around 2 V (approximately 40 mW) for red, orange, yellow & green, and 20 mA at 4–5 V (approximately 100 mW) for blue, violet and white.
Ultra-high output — 20 mA at approximately 2 V or 4–5 V, designed for viewing in direct sunlight.
Five- and twelve-volt LEDs are ordinary miniature LEDs that incorporate a suitable series resistor for direct connection to a 5 V or 12 V supply.