NANO EVERY!
IS NOT a Nano
No rebuttal?
Variable input voltage REQUIRES some method of regulation OR the regulator can be bypassed and power fed on the +5V line. It works. You are misreading the data sheet.
PS: Slow response due to 3hr power outage
There is a fundamental non-understanding regarding the NanoEvery and its 5V.
It is a DC-DC converter output, not a linear regulator output.
Placing an external 5V there is Bad.
Stop the Fake News --
MPM3610 in Arduino (Nano Every) - DC-DC Power Converters - Monolithic Power Systems' Technical Forum
Arduino seems to think they put a VIN pin on it.
It's like a doc snippets fight. Just because people argue doesn't make any of them right.
I hope that Jim can figure out that board doc for beginners does not power the word salad logic they make of it. Power can be sourced or sank, that doesn't make the power pins into OUTPUTs. Only IO pins can be OUTPUTs while yes for sure the power connected to the power pins can also sourve current which is external to the chip just like ground which is not an INPUT pin, it's the sink.
No.
You cannot / ought not apply an external 5V to the Nano Every's "5V".
It has an onboard SMPS and laying an external 5V there is improper.
You are correct!
Sorry for the late reply, I have been away from my computer.
Interesting discussion. Nothing here has changed my mind: a Nano Every can be powered through the 5V pin.
I have lots of Nano Everys, they have all been powered through the 5V pin at some time. They have all suffered exactly the same amount of damage that the bulldozer would have suffered had it been allowed to run over Arthur Dent: none at all.
While I've been away @madmark2150 has pretty much given my answer, but see below for more of my thoughts.
What is your basis for this claim? Experience? Something in the data sheet? Assumption?
I've had a quick look at the MPM3610 data sheet, I certainly have not read every word and could easily have missed something. If there's something relevant in there please point it out. I notice that in the Nano Every En is tied to Vin, and from the data sheet that Vin has to be high for the MPM3610 to be on. So, in the case of 5V on the 5V pin and Vin open circuit the MPM3610 will be shut down.
With any kind of power voltage regulator or converter used in whatever circuit there is always the possibility that, when the supply input is removed, whatever capacitors there are on the output maintain the output pin at or close to the output voltage after the input voltage has fallen to or close to 0V, this being the case I'd expect all regulators or converters to be designed to tolerate their output voltage being applied to their output pin from an external source while their input voltage is not present.
Finally, I don't ever remember seeing here a question along the lines of:
I powered my Arduino Whatsit by connecting 5V to the 5V pin and smoke came out of it.
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The NANO Every has a 5V pin and a VIN pin.
Do they BOTH connect to the DC Converter???
The 5V isn't coming from either the converter or the USB connect.
When USB supplies the board with 5V, does THAT go through the converter? What is the difference? Is there a circuit that only works when USB is connected?
How does 5V feed VIN? That includes 5V from USB and no other power.
I am soooooooooo mystified!
On the schematic there is VUSB, which I guess must be 5V, and there is 5V. There is D2, which links VUSB to 5V. D2 is PMEG6020 Schottky barrier rectifier with a Vf max of 530mV. So, when powering through the USB cable there is at least 4.47V on the output of the MPM3610. I don't understand how this could be OK but 5V from the 5V pin not be OK.
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Do you mean don't put 5V on the VIN pin that connects to the buck converter?
I love DC converters! Got some, tested 6V input and it worked fine! 5.5V (screw adjustable PS) gave me 5.0V out. Where I need decoupling caps, a tiny ripple is not a problem!
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It's got me. I know the chip but what else is on the board or why the would engineer a loss in capability puzzles me.
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Sorry but this is not correct. The Every has the 5V from the USB connected to the DC-DC converter output through D2 and this concept works. See attached extract from the Every schematic.
I would only supply external 5V on the Every 5V pin through a diode otherwise current might flow back and could destroy the USB or DC-DC converter.
I have my answer.
"Arduino Nano Every is designed to only receive external input supply via VIN, else you damage your board."
They did it on purpose.
I don't understand this statement. By 'flow back', where exactly do you mean? Do you mean back to the external power supply?
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IO pins are INPUT or OUTPUT.
IO pins moded as OUTPUT can source or sink limited current, the chip they are in will have a total max source and sink current limit too.
A power supply does ouput power but power and ground pins are not IO pins. They source or sink.
Pins moded as INPUT do not sink appreciable current. They charge internal circuits with about 1 microamp per read (328P datasheet) is all. An INPUT pin that is not read looks electrically neutral, the Z-state.
Engineering good practice says that you should only power a device from a single source at a time (omitting battery backup for now). So if you are using other than the USB for power, you should Isolate the usb power with a switch. I know they're not supposed to backfeed into the PC, but if the various items are mis sequenced during power cycle, things can get ... weird. While there are supposed to be power isolation components, I suspect this is an area where cotners are cut, especially with no name china-cheap clones. The belt & suspenders engineer in me says if I put in a hw switch, I'll ALWAYS have isolation no matter how much or how little isolation components are in the design.
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Yes, if you power the arduino through USB or Vin with the external 5V connected but powered down.
This is why D2 is already there: to prevent current flowing from the DC-DC converter to USB.
Nothing bad can happen if you have a diode feeding the Every 5V. You could power the Every from USB, Vin and the external 5V at the same time, the strongest will provide the 5V.
Just be sure that the external 5V is clean, no spikes, possible overvoltage, etc....
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Sorry but I disagree. Ex: The hard discs in raid arrays for servers are powered from minimum 2 power supplies and battery backup. When one of the supplies fails the hard disc continues to work.
Fully agree with this, it will work on an original Every but might not on a clone. Only the schematic of the clone can tell.