Timeline for If resistors do not decrease flow in a circuit then why are they able to make things like an LED short when otherwise it would without the resistor
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| Feb 13, 2018 at 9:52 | comment | added | pjc50 | @Django Well, that's a problem - for small LEDs the answer is usually 20ma. You might be able to make measurements of temperature and colour to work out whether you're overdriving an LED, but then you have no guarantee of its lifetime. This is why you should make sure you have datasheets or at least key ratings for components. | |
| Feb 13, 2018 at 2:23 | comment | added | Django | So how would I know how much mAmp an LED needs? If I have no info on an LED? | |
| Feb 12, 2018 at 13:09 | comment | added | Finkman | LEDs are (normally) current driven and if you have a voltage source and don't want to build a current-control, you can drive leds with a resistor in series. By doing that, you create a voltage divider. This causing a very basic closed-control loop where the current is regulated when the led changes it's voltage, which for example may be caused by temperature change. | |
| Feb 12, 2018 at 2:32 | vote | accept | Django | ||
| Feb 12, 2018 at 2:22 | comment | added | Django | It's starting to come together. The bicycle analogy makes sense. So electrons in a circuit are like linked? I always thought of electrons being 'individuals' in that if one is entering a resistor and slowing it down it has no effect on the others that are moving through the circuit on the other side. But Im confused on one thing. Why when people talk about powering LEDs they say they want XmA to run through it but when adding a resistor the mA stay the same? I thought we just established that resistors will slow down the current by transferring the energy from voltage into heat AKA lower mA | |
| Feb 11, 2018 at 9:33 | history | answered | pjc50 | CC BY-SA 3.0 |