# Serial inverter

With any digital chip, like with Arduino, you must not connect a data signal to any pin which is a higher voltage than the chip's Vcc pin, otherwise the chip can be damaged.

In your circuit, the IC will be powered by, let's assume, 4.5V. So your voltage divider must reduce the 5.9V signal to 4.5V for the IC's input pin.

The 6 inverter gates in the chip are identical. Connect the voltage divider output to the input of whichever gate you choose.

Yes.

No. You need any 74hc00- series chip containing simple, inverting, logic gates. The 74hc04 you found on Amazon, for example.

Another example is 74hc00, which is quad nand gates. A "nand" gate is an and gate with an inverted output. Connect one of its inputs to Vcc and you can use it as an inverter.

I'm not doing that, its going to be a separate power wire and a separate signal wire. The IC can handle 5V correct?

Ok, I'll connect it to the closest one from the arduino.

Noted, will ask if it can be sourced else I'll order it from Amazon.

So the input signal will be a higher voltage than Vcc, won't it? That's why you need the voltage divider.

74hc04 can handle up to 6V. So in theory you could power it with 5.9V and then you would not need the voltage divider on the input. But the Arduino will be powered at 5V maximum, and probably closer to 4.5V in your circuit, so you would need a voltage divider between the 74hc04 and the Arduino in that case. Either way, you need that voltage divider.

oh okay understood.

a pair of resistors will do right?

Yes. Google for "voltage divider calculator" to find a page which can calculate the correct values for you. Give it the input voltage of 5.9V and the output voltage of 4.5V (or whatever voltage your Arduino outputs at the 5V pin with 5.9V connected to Vin).

The important thing about a voltage divider is the ratio of the 2 resistor values. But the total value of the 2 resistors is not critical, anything around 5K to 500K will probably be ok.

Ok, will do.

Many thanks.

Here is a good voltage divider calculator:

https://damien.douxchamps.net/elec/resdiv/

I like this one because, unlike many, you give the input and output voltages required and it suggests the resistors. However, it does suggest quite low values for the resistors. For example it might suggest 100R and 33R. You can multiply both those values by 10 or 100 and it will not change the output voltage in your circuit. So you could use 1K and 330R or 10K and 3K3 for example.

I think it would be wise for you to post a schematic showing how you intend to wire everything together. Post that here and we can check it for you before you connect the circuit. Pencil and paper will be ok to draw the schematic.

i made a rough schematic in Fritzing. the 3 wires towards the bottom entitles the wires to the receiver.

this one is minus the serial inverter etc.

I couldn't find the exact display I have so I connected 4 pins randomly.

What you posted is not a schematic. It is Fritzing's "breadboard view". Switch to "schematic view" and add your receiver, inverter, voltage divider etc.

that's why I deleted the post and I'm trying to figure it out on my own.

I tried to find the receiver but there wasn't one on Fritizing, so I've just labeled the lines.

Am putting x2 photos, one schematic and one breadboard layout. Please advise on if I have done it properly, I tried to follow your instructions as best I could with the limited knowledge I have.

There is no need to delete posts (though it probably does not matter, it just looks bad). You just edit it and replace what you did not want with the "improved" version.

It's now clear that you are a complete beginner after all, and claims like

were either total BS or meant you have been copying such circuits without any understanding of how they work or how to adapt them to any other situation.

You need to put this project aside, it is too advanced for you at this stage of your learning and experience. Take a course or tutorial series for beginners in electronics. That will cover the basic knowledge you are currently lacking, such as how to draw a basic schematic, how a breadboard works, how to build the most basic circuits like voltage dividers etc.

Good luck and see you in a few months.

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I mean.

I have enough experience with coding, just not a lot with fritzing and electronics in general. I understand how breadboards and schematics work, and I took up this project on purpose to better my knowledge of electronics and how they work in general.

What I meant by this is that I've used transistors a lot more than logic gate circuits; wanted to get my point across hence exaggerated a bit. I appreciate your words and concern with my prowess and knowledge however I believe there is some misunderstanding in communication either by me or by you. As they say, programmers and electronics geeks aren't famous for their people skills; so I guess you can cut me some slack and so can I.

As for the schematic, I would have drawn it on paper however nobody would have understood my terrible handwriting

How about both you and I try to be clearer in communication from now on?

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@nightfury_11 take a calm look at your Fritzing image in reply #54 and tell me if the position of the 74HC139N on the breadboard is correct

Is that actually how you are using the breadboard ?

No lol, no way.

it was just a rough schematic as I mentioned in the post and after as well without any real clarity.

I assume that you can see why your understanding of a breadboard was brought into question

yes I can and I mentioned it in my deleted post.