Search Results
| Search type | Search syntax |
|---|---|
| Tags | [tag] |
| Exact | "words here" |
| Author |
user:1234 user:me (yours) |
| Score |
score:3 (3+) score:0 (none) |
| Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
| Views | views:250 |
| Code | code:"if (foo != bar)" |
| Sections |
title:apples body:"apples oranges" |
| URL | url:"*.example.com" |
| Saves | in:saves |
| Status |
closed:yes duplicate:no migrated:no wiki:no |
| Types |
is:question is:answer |
| Exclude |
-[tag] -apples |
| For more details on advanced search visit our help page | |
Results tagged with led
Search options not deleted
user 5340
An LED is a light-emitting diode. Lighting an LED is considered the "Hello world" of a circuit design, and it can be as simple as using a series resistor, or it can get more complicated, involving PWM and multiplexing.
15
votes
Accepted
Doesn't using resistors serial to LEDs all the time waste a lot of energy?
A typical red LED has a forward voltage drop of 1.8 V, and a maximum continuous current of around 20 mA.
Now what's our voltage? Lets say we want to use a 3 V source. … That is not really a lot of power, although it is a significant fraction of power consumption of the LED. The LED itself uses 1.8V * 20mA = 36 mW. …
- 811