Hey, I wanted to do a project, the link is down there. There's a 500 ohm resistor, I don't have one. Can I use 470 ohm one? Also I'll already say bye bye for comments like: "Make a project by yourself", "Using codes and circuits from internet won't teach you anything" || Project that I'm using
Also I'll already say bye bye for comments like: "Make a project by yourself", "Using codes and circuits from internet won't teach you anything"
This sounds very rude to me, asking a question and this is your attitude.......
but yes you can use a resitor of 470 ohm....
I just wrote that so people know that I am doing it for fun, sorry if it sounded rude for you and thanks for the answer!
Yes, you can use a 470Ω resistor. It is used to limit the current through the 7 segment LED.
There is a problem with that circuit, using a single resistor.
Because the current flowing through the resistor gets divided amongst the segments, then the more segments are illuminated, the dimmer they will be.
Thus when an '8' is displayed it will look dimmer than a '1'.
A better circuit would use one resistor for each segment.
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Thank you, I just finished making it and ill see how it works.
Oh yeah, it doesn't work right, I'll look for new code and circuit.
Actually it appears there are 2 500R resistors. Each connects one of the 2 common cathode pins of the display to ground. These two resistors are therefore connected in parallel and act like a single 250R resistor.
If you change both to 470R, they will act like a single 235R resistor.
Any of these values with protect the LEDs and the Arduino from too much current. But as @JohnLincoln said, the brightness will be different depending on what digit is displayed.
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I think I'll just look for another project. Thank you!
I recommend you waste no more time trying Instructables projects. There is no quality control on that site. As a beginner you will be unaware which are good projects/circuits/code and which are bad.
I suggest you try to find an interesting project on some other site, but before you start to build it, post a link to it on this forum and ask someone to check if it is a good project or not, and if not, what can be done to make it better.
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Could I use AI?
Could I use AI?
I asked chatgpt for a schematic for connection a 7 seg display to an Arduino
Here is what it gave.
+5V (Arduino)
|
[ Resistor ]
|
+-----+-------+
| |
| 7-segment display
| |
+-------------+
| | | | | | | |
A B C D E F G Common
| | | | | | |
| | | | | | |
| | | | | | |
+---+----+----+----+----+----+----+
| | | | | | |
Pin 2--|---A|----B|----C|----D|----E|----F|---|
| | | | | | |
Pin 3--- 4---- 5---6---7---8---9----10---|--> to GND or +5V
@jim-p Maybe, enclose your sketch inside a quote, for readability. I'm sure the OP has no clue what you posted, or it's significance.
Be our guest if you can give it the right questions and if you're able to differentiate between a good answer and a crap answer.
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This @jim-p response to what the OP wrote.
That AI thinks this is a schematic.
and neither do I.
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In general terms in electronics for most purposes the exact values of resistors is unimportant. In most cases 20% variation will not make any difference to anything. In some cases you'd get away with 100% or more variation, but that takes a little more judgement. Sometimes resistor values are critical (for measuring current for example), but that's the exception. No harm in asking if you're not sure.
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S'ok. I assumed (yes, I know) that you'd posted a properly formatted ASCII drawing, but that our glorious forum had stripped excess spaces. Happens all the time. I later realized poor old AI didn't know the difference, and produced that rubbish all by itself, probably from perfectly useful ASCII art shown elsewhere. Mea Culpa.
Put a 750 in parallel with a 1500, = 500.
Or a 33 in series with a 470, = 503.
Or just use a 510R
I asked ChatGPT for real for a schematic and got this response:
Summary
// Define segment pins
int segmentPins[] = {2, 3, 4, 5, 6, 7, 8}; // a, b, c, d, e, f, g
void setup() {
// Set all segment pins as output
for (int i = 0; i < 7; i++) {
pinMode(segmentPins[i], OUTPUT);
}
}
void loop() {
// Turn on all segments to display '8'
for (int i = 0; i < 7; i++) {
digitalWrite(segmentPins[i], HIGH); // HIGH for common cathode
}
}
