# Tag Info

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There is a linear regulator such as LM1117 on the Arduino (and clone) boards you mention. The MCU chip itself does not draw much current, but if you draw current from the GPIO pins or connect something that draws a lot of current to the 5V pin the regulator will get very hot if the input voltage is too high. So, while you can use 12V (and the LM1117 can ...

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If you buy a battery it is labeled + or - on each end. The + side [end] is ... Don't worry about electrons. Current flows from positive to negative when you make a circuit. Resistors limits the current/amps but keeps the voltage the same. Correct? Yes, if you don't overload your battery. The battery has some internal resistance and when you connect a load ...

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Yes, you can put a carefully selected resistor across the terminals of a battery with no ill effects. Key phrase is "carefully selected." Current may be described in two seemingly opposing ways. You may want to look at is as if the positive charge moves, or if the negative charge moves. If you are talking about current flow in metals, then you are ...

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In electronics, you usually don't have to worry about batteries having atoms and electrons. It can be simply modeled as voltage source that can provide current through some amount of internal resistance. Modeling how battery actually works is usually not necessary, unless you are doing something where it matters. Current as we draw it flows from positive ...

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In my experience ORP/pH sensors are not really suitable for other things. Also they need to be calibrated quite often (lab practice is 8 hour intervals). Given that an ORP sensor is essentially a redox indicator it will probably have a huge cross sensitivity to other elements (probably bromine, iodine and such) Chlorine in water AFAIK in lab is usually ...

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Yes. Only the LED strips and the power input to the Arduino ($\text V_{IN}$) see the 12V. Suggest adding a resistor on the D6 output. Of course the LED strips must be the programmable WS2812 type (or compatible) for it to work. The pots and switch connect to the 5V output from the on-board regulator AMS1117 of the Nano (+5V pin). Do not use automotive 12V ...

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No, the Nano takes a 5V power supply. 12V will kill it in an instant. If you have a 12V supply you will need to use a voltage regulator or other voltage converter to get 5V to supply the Nano. Keep in mind that the Nano's input/output pins are NOT 12V tolerant. So you will need to ensure that you keep all voltages that the pins are exposed to at 0-5V. A ...

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There are two ways that you can use a Zener in your circuit. Neither is all that good. First, there's the standard "shunt regulator" circuit. It looks like this: simulate this circuit – Schematic created using CircuitLab You have to size R1 to provide the full current to the nRF24L01 at 3.3V. That's about 14 milliamperes. That also means ...

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Looks like the blue and yellow wires are going to the motor and the other wires are an encoder? 5K pot for position sensing? Looks like that was used as limited rotation servo. Component on the back of the motor looks like a filter capacitor to try to keep commutator noise out of the control circuit. Use a full Bridge motor driver to control the motor on the ...

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Thank you all for the information in the comments. I'm composing them the best I can into an answer. I believe I now understand: The 10K resistors are a "pull down" to prevent potential indeterminate state issues. The 220r resistors are to protect the MCU from potential current spikes. I don't intend to create a Schematic for the 3 examples in the ...

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I would expect something like this. I assume the green wire header ABC V+,0V are the 3 phase Hall Sensor inputs. simulate this circuit – Schematic created using CircuitLab Power Off switch at full CCW and Power ON at low Speed only. FWIW I am doing a similar project this winter to my 100W 3phase BLDC attic Fan which will be controlled by a wireless ...

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You can and must connect the grounds together. It's the common reference. The only other thing wrong with your Fritzing picture is that you are feeding the ADC 12V voltage, divide it down with a simple voltage divider with two resistors. You don't need to measure the GND with the ADC.

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An Iridium 9603 module is the smallest satellite comms device that I know of. It’s about the same size as a patch antenna (which you’ll unavoidably need).

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If those are the parts on hand, this circuit should work. Resistor values are not critical and could be anything between 1K to 100K or so. Which transistor to use doesn't really matter much. The IRLZ44 has slightly lower RDSon so using that to switch the load is better. link

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