LED polarity on Slow Loris

[Adamo]

How should I align the 2 led's on the Slow Loris build. Does the square pad represent '+' round pad represent '-'?

[mgwhit]

Square pads are typically used for the + side of polarized components, although this is not a hard and fast rule.  In this case, since the clipping LEDs are arranged antiparallel, it doesn't matter -- as long as you are consistent.

[Adamo]

That's a relief! That's how I did it but then I saw that on diodes, the square pad aligns with the cathode.

Thanks!

[TGP39]

Hi Adamo,
      I had the same problem regarding polarity orientation for LED's.  Matthew is correct when he says that most PCB's utilize the square hole for the positive (anode) side of the led.  The only problem is that not ALL PCB's follow this rule. So how is a builder suppose to know which rule to follow?  The answer is the schematic.  All schematics should show you the proper orientation of the Led by indicating the bar(cathode) side of the LED (just like any other diode).    Take a look at the following picture I found on the internet:




Remember this line....."Short and Fat Cathy Lives at the Bar".   This means the following rules:

A. Cathy (Cathode) is always where the bar is on the schematic.
B. Cathy (Cathode) is the shorter leg of the LED.
C. Within the epoxy case of the diode is two foil looking, jagged pieces. Those two pieces make up what is called the lead frame. All you have to remember is that the fatter piece of foil (called the anvil) aligns with the cathode. Alas, Cathy is fat also. 

Finally, on Brian's PCB and many others, they attempt to help the builder properly orient the led by showing a silkscreen image of an led. The image shows a flat side and a curved side. The flat side is where the Cathode goes. I guess you could say Cathy is flat chested as well.

I hope these little tips will not only get you past the Slow Loris, but all your future builds as well.

Steve.

[selfdestroyer]

Remember this line....."Short and Fat Cathy Lives at the Bar".

Thanks for that, now I will never get that out of my head. lol

Cody

[TGP39]

Remember this line....."Short and Fat Cathy Lives at the Bar".

Thanks for that, now I will never get that out of my head. lol

Cody

That's the idea. 

Steve.