LED's vs Resistors vs Capacitors

I’m trying to get my head around the correlation between the Resistors and Capacitors needed for the number of LED’s. Now I understand it depends on the LED being used. I’m no electrician, but is there a guide to show how to figure this our?

5mm 1.8 v red LED, 220 resistor,

What I’m trying to build is a light board which will access the internet and flash upon certain criteria. The board could have up to 35 lights, or 5 smaller boards with 7 lights and then linked together somehow.

Any help is much appreciated


I fond this book on Amazon, It has 5 star reviews. It may be a worth while investment… https://www.amazon.com/dp/B01D5LXUYI/ref=wl_it_dp_o_pC_nS_img?_encoding=UTF8&colid=2LWZPONMMR4IO&coliid=I2ETGHTHX30P6S#navbar

Thanks for the reply and link. It has been added to the wishlist. $30.00 seems like a small investment. I looked at the preview pages and knew there would be math involved. Don’t mind math, just didn’t want to go back to school. Hopefully most of the stuff will bring back some high school math.

There are calculators on the web that will figure a lot of this stuff out for you. Texas Instrument has a calculator for buck regulators, enter the type, voltage, and amperage and it will give you a bill of materials and a schematic. The book will really help with the fundamentals and the understanding on how everything works.

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I use whatever resistor equalises the brightness, when using different colours - blue is super bright and yellow is dull -.

You might want to get a Decade Programmable Resistor Board, and suck-it-and-see.


@smilliken, Here are some cool little calculators on the Digi-Key site for LEDs, resistors, capacitors, etc.: http://www.digikey.com/en/resources/online-conversion-calculators

Check out some of the other Digi-Key Resources, there is a lot of need stuff to learn from…

Fantastic. I had previously register on that site but never saw that, thanks. Looks handy.

I have purchased the book Fritizing by Simon Monk as well. Good, easy read.

Found this as well. http://led.linear1.org/1led.wiz

Now is this per LED? So One resistor for one LED.