# Tag Info

4

There is no governing body that decides what is "standard" in a microcontroller. You must always check the datasheet.

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Would this circuitry work with 5.1V Zener diode to protect a Nano input? Short answer: NO A Zener is crude when it comes to use as a clamp, and the voltage variation will impact the A/D conversion on your Arduino Nano. A typical Zener such as this has a range of voltage from 4.85 - 5.2 V for a nominally 5.1 V Zener. At 5.2 V you will already have ...

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Assuming the MCU pin will be damaged/destroyed if configured as Output, when externally forced to some fixed level, yes, you should insert 10Kohm resistor in the pin's PCB trace. Do not configure the pin with any on-chip pullup or pulldown current.

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I believe this is similar to the answer described above, but I am unsure how to run the simulation. However when I tried it in Eagle using ngspice, I got a low voltage on Rload ie. only 1.6v even though the voltage on the gate was 0.046 (wrt gnd) The fet should be fully on at this point (I thought) simulate this circuit – Schematic created using ...

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As a quick-and-cheerful experiment there isn’t anything inherently wrong with this really, but it could be improved. Out of reset the MCU will set the pin as an input. The worst that can happen is if you make a programming error and change the port function or direction such that it's an output. The resulting current is limited by the Rds(on) of the port ...

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Yes there is. Many, but you will find none of them won't do exactly what Proteus does. Some only emulate the AVR itself. Some have a schematic editor so you can attach other components to it like in Proteus. For example SimulIDE and simutron.

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Does your switch break-before-make or make-before-break? If the latter, a resistor is needed to prevent a short from 5V to ground. The resistor should be between the switch and 5V, or between the switch and ground. Setting D2 as an output can cause that output to source/sink very large currents. This may cause the processor to behave incorrectly, or in ...

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This was bumped to top but I presume the problem has been long solved, one way or the other, still in general here are some thoughts of dealing with very noisy signals. The very first thing that comes to mind is: Why are the signal and power wires running in the same cable? Is there any reason why you couldn't do that with a separate shielded cable? That ...

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Page 258 of datasheet you linked says: Maximum voltage on any pin except RESET with respect to ground VCC+0.5V So it is ok, I hope speed is not a problem, remember that diode behaves like a capacitor, and as you see it is in parallel with a resistor.

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If I drive the microcontroller pin high that means the zener diode will conduct and the input pin will detect the high voltage. With an output pin high at 3.3 volts, the voltage after the zener diode (2.9 volts) will be 0.4 volts at the input pin and not enough (possibly) to rise past the lower limit for detecting a logic 1. It sounds like a problem to me ...

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The binary image only provides the contents of the Flash ROM memory; it does not provide an "image" of the RAM. Once programmed, the microcontroller does the same thing every time you turn it on...that wouldn't be possible if we tried to download data to the RAM as part of the programming process, because the RAM data is not saved when we cycle power. Now, ...

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If you have a bit more detail about your feedback circuit (where the pot wiper goes) that would be helpful, as well as the resistance values used for the pot and its load resistor. I'm thinking an optoisolator like this one: https://www.digikey.com/product-detail/en/on-semiconductor/H11G1SM/H11G1SM-ND/1793958 could be used to modify the voltage divider ...

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Quick Answer The equivalent impedance at P.O.I. is simply the two resistors in parallel $R_1 \parallel R_3$. Detailed Answer We make the following assumptions in this analysis: The node IN has "infinite" input impedance -- its impedance is high enough that near-zero current flows through $R_2$ and so $R_2$ has no influence on the equivalent ...

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There's no specific requirement for brown-out detect. However, typical product testing will involve testing low-line conditions and power-on / power-off cycling. Thus, a good design will include a circuit that guarantees correct startup and shut down. For example, PC power supplies as part of the ATX spec include a "POWER GOOD" signal, that informs the rest ...

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