Power LED from 3.3V Power Pin without Resistor





.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ margin-bottom:0;
}







2















I tried wiring one white LED to the 3.3V pin on a Pi Zero W with a 330 Ohm resistor but it's not as bright as I would like. If I wire it up without a resister I get a good amount of brightness. Is that a viable solution? Or should I try a smaller resistor?



If it matters, the power supply is a standard 5V 2.5A supply like this one. The LED is this one.










share|improve this question


















  • 1





    I'd recommend 10Ohm resistor

    – Jaromanda X
    44 mins ago


















2















I tried wiring one white LED to the 3.3V pin on a Pi Zero W with a 330 Ohm resistor but it's not as bright as I would like. If I wire it up without a resister I get a good amount of brightness. Is that a viable solution? Or should I try a smaller resistor?



If it matters, the power supply is a standard 5V 2.5A supply like this one. The LED is this one.










share|improve this question


















  • 1





    I'd recommend 10Ohm resistor

    – Jaromanda X
    44 mins ago














2












2








2








I tried wiring one white LED to the 3.3V pin on a Pi Zero W with a 330 Ohm resistor but it's not as bright as I would like. If I wire it up without a resister I get a good amount of brightness. Is that a viable solution? Or should I try a smaller resistor?



If it matters, the power supply is a standard 5V 2.5A supply like this one. The LED is this one.










share|improve this question














I tried wiring one white LED to the 3.3V pin on a Pi Zero W with a 330 Ohm resistor but it's not as bright as I would like. If I wire it up without a resister I get a good amount of brightness. Is that a viable solution? Or should I try a smaller resistor?



If it matters, the power supply is a standard 5V 2.5A supply like this one. The LED is this one.







power led






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 1 hour ago









MichaelMichael

1504




1504








  • 1





    I'd recommend 10Ohm resistor

    – Jaromanda X
    44 mins ago














  • 1





    I'd recommend 10Ohm resistor

    – Jaromanda X
    44 mins ago








1




1





I'd recommend 10Ohm resistor

– Jaromanda X
44 mins ago





I'd recommend 10Ohm resistor

– Jaromanda X
44 mins ago










1 Answer
1






active

oldest

votes


















3














You need to consider that the forward voltage of a white LED is likely in the range of 3.0 V to 3.2 V (according to the linked article). Assuming the best case of 3.0 V and a resistor of 330 Ohms and using Ohm's law R = U / I we find that the current is about 1 mA and thus the brightness of the LED is rather low. Decreasing the resistor will help to some degree but be aware that this is borderline in any case. Say 33 Ohms will get you about 10 mA which might be ok. Best bet is to use the 5 V instead and design the resistor in such a fashion that the current suits the safe operational range of the LED.



Connecting a LED to a voltage source without a current limiting resistor is not a safe way of operating a LED. It is therefore not advisable to do so.



Find a more elaborate description of the calculations here; even though it is aiming at GPIO pins the physics still apply.






share|improve this answer
























  • Great input - thanks so much!

    – Michael
    36 mins ago












Your Answer






StackExchange.ifUsing("editor", function () {
return StackExchange.using("schematics", function () {
StackExchange.schematics.init();
});
}, "cicuitlab");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "447"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fraspberrypi.stackexchange.com%2fquestions%2f98051%2fpower-led-from-3-3v-power-pin-without-resistor%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









3














You need to consider that the forward voltage of a white LED is likely in the range of 3.0 V to 3.2 V (according to the linked article). Assuming the best case of 3.0 V and a resistor of 330 Ohms and using Ohm's law R = U / I we find that the current is about 1 mA and thus the brightness of the LED is rather low. Decreasing the resistor will help to some degree but be aware that this is borderline in any case. Say 33 Ohms will get you about 10 mA which might be ok. Best bet is to use the 5 V instead and design the resistor in such a fashion that the current suits the safe operational range of the LED.



Connecting a LED to a voltage source without a current limiting resistor is not a safe way of operating a LED. It is therefore not advisable to do so.



Find a more elaborate description of the calculations here; even though it is aiming at GPIO pins the physics still apply.






share|improve this answer
























  • Great input - thanks so much!

    – Michael
    36 mins ago
















3














You need to consider that the forward voltage of a white LED is likely in the range of 3.0 V to 3.2 V (according to the linked article). Assuming the best case of 3.0 V and a resistor of 330 Ohms and using Ohm's law R = U / I we find that the current is about 1 mA and thus the brightness of the LED is rather low. Decreasing the resistor will help to some degree but be aware that this is borderline in any case. Say 33 Ohms will get you about 10 mA which might be ok. Best bet is to use the 5 V instead and design the resistor in such a fashion that the current suits the safe operational range of the LED.



Connecting a LED to a voltage source without a current limiting resistor is not a safe way of operating a LED. It is therefore not advisable to do so.



Find a more elaborate description of the calculations here; even though it is aiming at GPIO pins the physics still apply.






share|improve this answer
























  • Great input - thanks so much!

    – Michael
    36 mins ago














3












3








3







You need to consider that the forward voltage of a white LED is likely in the range of 3.0 V to 3.2 V (according to the linked article). Assuming the best case of 3.0 V and a resistor of 330 Ohms and using Ohm's law R = U / I we find that the current is about 1 mA and thus the brightness of the LED is rather low. Decreasing the resistor will help to some degree but be aware that this is borderline in any case. Say 33 Ohms will get you about 10 mA which might be ok. Best bet is to use the 5 V instead and design the resistor in such a fashion that the current suits the safe operational range of the LED.



Connecting a LED to a voltage source without a current limiting resistor is not a safe way of operating a LED. It is therefore not advisable to do so.



Find a more elaborate description of the calculations here; even though it is aiming at GPIO pins the physics still apply.






share|improve this answer













You need to consider that the forward voltage of a white LED is likely in the range of 3.0 V to 3.2 V (according to the linked article). Assuming the best case of 3.0 V and a resistor of 330 Ohms and using Ohm's law R = U / I we find that the current is about 1 mA and thus the brightness of the LED is rather low. Decreasing the resistor will help to some degree but be aware that this is borderline in any case. Say 33 Ohms will get you about 10 mA which might be ok. Best bet is to use the 5 V instead and design the resistor in such a fashion that the current suits the safe operational range of the LED.



Connecting a LED to a voltage source without a current limiting resistor is not a safe way of operating a LED. It is therefore not advisable to do so.



Find a more elaborate description of the calculations here; even though it is aiming at GPIO pins the physics still apply.







share|improve this answer












share|improve this answer



share|improve this answer










answered 43 mins ago









GhanimaGhanima

12.6k114080




12.6k114080













  • Great input - thanks so much!

    – Michael
    36 mins ago



















  • Great input - thanks so much!

    – Michael
    36 mins ago

















Great input - thanks so much!

– Michael
36 mins ago





Great input - thanks so much!

– Michael
36 mins ago


















draft saved

draft discarded




















































Thanks for contributing an answer to Raspberry Pi Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fraspberrypi.stackexchange.com%2fquestions%2f98051%2fpower-led-from-3-3v-power-pin-without-resistor%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

香粉寮

GameSpot