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Questions relating to designing PCBs
By harrison0550
#187748
I have recently designed and sucefully had my first prototype ran for a simple power Distro PCB. This is exciting for me as creating a PCB in eagle is something I have wanted to do forever and thanks to the tutorials on spark fun I was able to make it happen. All the components on it are THT and I have no experience with SMD components. My current board design is below but I am now looking at making a RevB design with SMD led's to light up when a fuse is blown on the board.

RevA design.....
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This is where my question comes in. For the RevB I would like to add some led's to the board to display when a fuse is blown. I have been reading different approaches online and frankly I'm lost. I have found this schematic.....
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It seems simple enough but I could use suggestions on what components and sizes are most popular and readily available by most board houses so I can keep cost down. I am planning on separating the fuse holders slightly and placing the SMD components between each fuse holder. Also several of these boards will be used by 5v supplies and several others will be attached to 12v supplies. I'm not sure if that makes a difference or not in choosing these components.

My largest amount of confusion came when I found this board online today that appears to only be using 2 components to identify a blown fuse.....
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And
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As you can see I'm not really sure what avenue to take here adding the blown fuse led indicator as the interwebs have done a very good job at confusing me today and leading me down several different paths. Any help here would be greatly appreciated. Thanks!
By lyndon
#187762
An LED in series with a high-value resistor, that combination in parallel with the fuse will likely do what you want. It's also easy enough to test: try building the circuit and substitute a switch for the fuse.
By Newbie10
#188185
Your own circuit is the right one. The LED will light up if the fuse is blown whether the output is loaded or not. The "simple" system of connecting the LED-series resistor in parallel with the fuse is OK, but if there is no load connected the LED will not be lit as there is no current path for the LED.