simple Q about arduino pro mini

in [ uno & mega arduino pages ] is written [ input voltage (recommended) : 7 - 12 V ] , but in [ pro mini arduino page ] isn't written [ (recommended) ].

does it mean that it's hard to happen drop voltage in arduino pro mini ?

Top left corner of the pdf https://www.arduino.cc/en/uploads/Main/Arduino-Pro-Mini-schematic.pdf

Microcontroller ATmega328 Operating Voltage 3.3V or 5V (depending on model) Input Voltage 3.35 -12 V (3.3V model) or 5 - 12 V (5V model) Digital I/O Pins 14 (of which 6 provide PWM output) Analog Input Pins 6 DC Current per I/O Pin 40 mA Flash Memory 32 kB (of which 0.5 kB used by bootloader) SRAM 2 kB EEPROM 1 kB Clock Speed 8 MHz (3.3V model) or 16 MHz (5V model)

Also on the Arduino Pro Mini page:

https://www.arduino.cc/en/Main/ArduinoBoardProMini

Input Voltage 3.35 -12 V (3.3V model) or 5 - 12 V (5V model)

It's more complicated than that. Minimum input voltage is the model's rail voltage plus the regulator's dropout voltage (3.45volt or 5.15volt). They will still work at lower voltages. But the supply is out of regulation, and e.g. A/D readings become unstable. Maximum of the regulator is 20volt, but the input cap is rated for 16volt. So max supply is 16volt for both models. I doubt you can power any sensors or drive any current consumers at 16volt in without overheating the tiny regulator. Leo..

Wawa:
It’s more complicated than that.
Minimum input voltage is the model’s rail voltage plus the regulator’s dropout voltage (3.45volt or 5.15volt).
They will still work at lower voltages.
But the supply is out of regulation, and e.g. A/D readings become unstable.
Maximum of the regulator is 20volt, but the input cap is rated for 16volt. So max supply is 16volt for both models.
I doubt you can power any sensors or drive any current consumers at 16volt in without overheating the tiny regulator.
Leo…

Is there problem if I make electronic device with [ arduino pro mini ] and connect 5V to ‘VCC’ pin,
or it’s recommended to connect >5V to ‘RAW’ pin?
which is better?

as I understand it “RAW” is for incoming power.
“VCC” is 5 volts output to your sensor.
I don’t believe the pro mini can handle up to 12 volts though.
I ran one on my desk for a half hour at 11.1 volts and I watched the LED flicker and then go out,.
I could never get it to power back up after that.
Now I use a 5 volt BEC, it’s like a tiny switching power supply.

It's not more complicated than that the pdf shows how the thing is made and where to hook power to it at and at what voltage level. The op should read it and under stand it. And all answers should be based on it.

Or he will be back saying something burned up.

The RAW pin is the input to the regulator i would stay under 9 volts because it's not installed looking at one of these with a good heat transfer. And the board does not look to be made to source much more then maybe 200 mA.

And the VCC pin is for regulated 3.3 or 5 volt supply. But make sure SJ1 is open it's a solder jumper if it's not open you'll back feed the regulator.

TTU.ABD:
Is there problem if I make electronic device with [ arduino pro mini ] and connect 5V to ‘VCC’ pin,
or it’s recommended to connect >5V to ‘RAW’ pin?
which is better?

RAW (Vin) is pre onboard voltage regulator.
THIS Arduino uses a regulator with 0.1-0.15volt dropout. So only 5.15volt is needed for a 5volt model.
The 7volt you see in other posts relates to models with a different regulator. UNOs, MEGAs etc.

You CAN feed <=5volt straight on the VCC pin (MCU supply). Absolute max on this pin is 5.5volt!
To stop “backfeed” in this case, you can remove/unsolder a link on the board.

Which is better?
Depends on the application.
Battery or mains supply. Do you use the A/D etc.
Post your circuit/sketch.

be80be:
The RAW pin is the input to the regulator i would stay under 9 volts because it’s not installed looking at one of these with a good heat transfer. And the board does not look to be made to source much more then maybe 200 mA.

The regulator is rated for ~150mA. That leaves ~100-120mA for sensors/LEDs etc.
Looking at the datasheet, and making an educated guess, I would keep power dissipation under 0.5watt (stinking hot).
That puts max input voltage indeed at ~9volt (for the 5volt model).
Leo…

Please could someone advise me real quick... If I was to try and build an Arduino compatible circuit based on the Pro Mini schematic for 3.3v / 8Mhz... should SJ1 be open or closed?

( https://www.arduino.cc/en/uploads/Main/Arduino-Pro-Mini-schematic.pdf )

Unless you are applying 3.3v through the VCC header pin close SJ1 which a solder bridge.

BTW Putting ( ) around a URL makes it difficult the use on an iPad. .