why does the luxeon k2 have four leads and a zener diode?

[Jbcourt]

Please help

 

[bshanahan14rulz]

extra leads to handle current and zenier to handle esd.

 

[Jbcourt]

What is esd?

 

[Illum]

electrostatic discharge, occurs when a high electrostatic field develops between two objects in close proximity, one of the major causes of device failures in the semiconductor industry...basically like a surge voltage that fries junctions and chip weevils in short notice

 

[tebore]

Actually only 2 of the 4 leads supply the power to the die. The extra legs are actually there to give the LED better mounting. All power LEDs (well the ones that aren't knock offs) have some type of diode to protect them from ESD.

 

[Black Rose]

Actually only 2 of the 4 leads supply the power to the die. The extra legs are actually there to give the LED better mounting.

Are they clearly marked which ones are for power and which are for mount support?

 

[tebore]

On the emitter itself no. On the data sheet yes.