Arduino mini, pro mini power consumption

Hi all, I'm making a project with arduino (nano, mini or Uno)that requires low power consumption. I read Nick Gammon's post about: Power saving techniques for microprocessors. After experimenting with arduino Uno, I got similar voltage readings running with the vIn pin and the 5v pin. I also read other posts regarding the topic. (sleep_watchdog_battery, The Shrimp and several more...)

I'll very appreciate it if you can help: 1. When trying the bypass a voltage regulator, for example on the arduino Uno, and connecting a 5v power source to the 5v pin, are the only components consuming power are: the USB chip, LEDs and the atmega chip? 2. Looking at arduino mini and arduino pro mini, Do they consume more power then "the shrimp" or then the Atmega328 processor on its own - the "Bare-bones board" from Nick Gammon's post? If they do, by what components?

From what I understand, the pro mini has a voltage regulator and the mini doesn't, So the pro should consume more than the mini. Am I wrong?

Thanks

If you want a regulator-less board, try a runtime board from nkcelectronics http://www.nkcelectronics.com/arduino-runtime-board-rev-b.html build up just the parts you want or try one of my surface mount boards for something smaller PL & schematic here http://www.crossroadsfencing.com/BobuinoRev17 scroll down towards the bottom.

The Mini and ProMini both have regulators. The Promini regulator can be bypassed and the board supplied with 5V, I have about a dozen of them running that way, with an offboard 7805 supplying 5V to the Vcc pin.

Thanks CrossRoads.

I asked about Arduino mini, pro mini because I have very easy access to them. I can assemble the bare-bones board, and I like it a lot.

I didn't know the mini had a regulator.. thanks! Can anybody explain if it's understood from this link? http://arduino.cc/en/Guide/ArduinoMini

If I supply 5v to the 5v pin on the mini, won't I bypass the regulator if it's there?

I'm still interested to know, if I bypass the voltage regulator in the pro mini, and supply 5v to the 5v pin, is it going to consume more power then "the shrimp" or than the Atmega328 processor on its own - the "Bare-bones board" from Nick Gammon's post?

Are there any components on the pro mini that consume power, other than the regulator (and the atmega chip)?

Thanks

Hi again,

I managed to find a post that might answer this question: http://codehackcreate.com/archives/166

According to this, using arduino pro mini 3.3v and supplying 4.5v to the RAW power pin: With the "ArduinoSleepCode" he managed to get ".. around 200 microamps..". So he got a current draw of 200uA without turning the ADC, PRR, LED, etc... off. I wonder how low can the current draw get if we implement Nick Gammon's guide: "Power saving techniques for microprocessors"

If anybody can confirm this data, or experimented on the manner, please reply what you think.

When I get an arduino pro mini, I'll check and post the results myself...

Thanks

around 200 microamps

That actually is fairly high but it is a function of how you want your chip to operate.

The power LED on the promini consumes power. I have an 8 MHz promini based remote control that I power via Vcc pin with unregulated 1000mAH LiPo battery. Has a 434 MHz Tx module with it. The unit seems to draw ~9mA when not transmitting and jumps to ~15mA when transmitting, measured with a multimeter. Keep meaning to rebuild it using standalone '328p, never seem to get to it. Lasts about a month between charges. Max1811 controls the battery charging from 5V source.

Hi dhenry, yes 200uA is high. But keep in mind that according to Nick Gammon's "Power saving techniques for microprocessors" post, turning off ADC lowered the consumption "...down from 335 uA to 0.355 uA...". So 200uA is not the end of the road here.

CrossRoads, among other things, I intend to create a remote also using the 433mhz. How far do you get it to work? Open space or between rooms? In this link I sent before it's mentioned that without using "ArduinoSleepCode", he also got around 10mA, but after using "ArduinoSleepCode" he got 200uA. That's my point here. That you can get 200uA and far less consumption, just by using "ArduinoSleepCode" and following Nick Gammon's post.

I almost have all the parts to build a standalone arduino, and maybe get an arduino pro mini. I think, after reading that link I sent, that with pro mini I'll get very close (if not the same/better) consumption to the standalone aduino 328. very close for me is around +-100uA, and willing to live with 500uA difference to save the trouble of building the standalone arduino. Plus the pro mini is lighter, and that's important to my flying projects.

If anybody experimented with any of this, please reply what you think.

Thanks

Hi all,

I have a project that i've completed with the Arduino Uno R3. I want to purchase and use the Arduino Micro due to its smaller footprint. I've read your comments on the Arduino Mini and Pro Mini regarding their power requirements.

Does the Arduino Micro require a separate 5V regulator for its power source? Does it have a built in regulator?

And...with the exception of a few more analog and digital I/O pins on the Arduino Micro, can I expect the exact same functionality as I currently have with the Arduino Uno R3?

Any details will help,

Thanks!

My remote works at least 50' as that's how big our fencing club is. Tx & Rx use 17cm of 30 guage wirewrap for antenna.

Arduino Micro: Input Voltage (recommended) 7-12V Input Voltage (limits) 6-20V

So yes, it has a voltage regulator.

Microcontroller ATmega32u4 So more like a Leonardo than an Uno.

mark76a: I'll very appreciate it if you can help: 1. When trying the bypass a voltage regulator, for example on the arduino Uno, and connecting a 5v power source to the 5v pin, are the only components consuming power are: the USB chip, LEDs and the atmega chip?

No, there's a second atmega chip on there as well...

mark76a: 2. Looking at arduino mini and arduino pro mini, Do they consume more power then "the shrimp" or then the Atmega328 processor on its own - the "Bare-bones board" from Nick Gammon's post? If they do, by what components?

There's not much fat on a pro mini, no. You can also get very basic boards without all the extra junk, eg. http://evilmadscience.com/productsmenu/tinykitlist/180

Applying 3.3V to the VCC pin of an 8MHz Pro-Mini, I measured a minimum current draw of approx 1mA. That’s with all MCU peripherals disabled, and the CPU in power-down (the deepest sleep mode available).

Then I cut a PCB trace to isolate the regulator and power LED, as shown below. With this small modification, I could get the current draw down to <3uA (which is the error of my meter).

The cut can be undone by shorting the two VCC pins together. NB the Pro-Mini PCB has been redesigned since then, so check that this mod is still possible before buying.

I'll have to try that with my remote!

Thank you Crossroads,

this voltage consumption topic is great!

Much appreciated!

Do you know if the voltage regulator circuit waste some power if we provide the voltage through VCC? Is the led the only responsible for consumption voltage drop from 1mA to <3uA?

Interesting thread,
Thank you

The power LED draws about 0.2mA; the remainder is drawn by the regulator.

Hi,

Very interesting post. Here is my contribution, I use an Arduino Mini powered at VCC Pin with 3,7V. My consumption is about 2.4mA by using following sleep code :

void sleepPwrDown(uint8_t wdt_period) {
  wdt_enable(wdt_period);
  wdt_reset();
  WDTCSR |= _BV(WDIE);
  set_sleep_mode(SLEEP_MODE_PWR_DOWN);
  sleep_enable();
  power_adc_disable();
  power_spi_disable();
  power_timer0_disable();
  power_timer1_disable();
  power_timer2_disable();
  power_twi_disable();
  sleep_mode();
  wdt_disable();
  WDTCSR &= ~_BV(WDIE);
}

Here are hardware schematics : http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Dev/Arduino/Boards/Arduino-Pro-Mini-v13.pdf http://arduino.cc/en/uploads/Main/arduino_mini_schematic05.pdf

According to measures given previously for ProMini, consumption on Mini seems excessive. Does it comes from - 16Mhz ATmega 328 frequency? - regulator? in both cases it is not used (on my Mini Arduino nothing is connected on 9V Pin) -other circuitry?

Any help appreciated. Thanks.

The power LED on the Arduino Mini is driven via a 1k resistor, whereas the ProMini has a 10k resistor. That probably accounts for the difference. To get really low power consumption you'll need to disconnect the LED and regulator.

Tim7,

No more LED! 1K resistance does the difference, I decrease consumption of ~2mA ! No I'm below I'm in hundreds of µAmp domain! Cheers

I'm doing the same experiments here with a pro mini and an nRF24l01 radio.

I'm also experimenting with a boost converter which will go from 0.9V to 5V in and give 5V out.

I have a 5v pro mini which means I have to waste some power with a 3.3v regulator for the radio. The PIR I have needs 5v so I can't go all 3.3v.

Running as standard I get 18mA on the pro mini and 15mA to the radio.

I tried moving the 5v input from RAW to VCC and actually saw an increase of just over 1mA so I will take a look at disabling the regulator and power leds next.