Can I increase the 5V amparage without destroying my arduino uno

Thread Starter

Miquel19

Joined Aug 16, 2020
37
Hi everyone. These days I have been finishing my project, but I have found the last problem. I'm almost new to the electronics world, so it will be amazing if someone can advise me. I'm trying to use all these components at the same time. The problem is that I don't know if the Arduino can support that much amperage. The Arduino its powering the Wemos D1 mini, 8x8 led matrix, and the DFPlayer mini with his respective speaker, and I don't think that the 5V pin could afford that much. Do you have some Ideas on what can I do? (the battery is not 12V, I'm using 9V)Cotxe_1.2.png
Thanks in advance
 

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dl324

Joined Mar 30, 2015
11,926
The Arduino its powering the Wemos D1 mini, 8x8 led matrix, and the DFPlayer mini with his respective speaker, and I don't think that the 5V pin could afford that much. Do you have some Ideas on what can I do? (the battery is not 12V, I'm using 9V)
The voltage regulator says it can handle over 1A and has self protection. But the problem with that is that the Arduino may not run if it starts shutting down.

Your best bet is to design your other circuitry to operate from whatever voltage you're using to power the Arduino; or calculate the maximum all of the extra circuitry will draw and convince yourself that the Arduino regulator can handle the load.
 

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Irving

Joined Jan 30, 2016
1,070
As AH said, measure it under worst-case conditions - full volume, all LED on, wifi transmitting.

At a rough estimate
DFplayer 20mA idle, @ 1.5W output ~100mA
LED Matrix 8mA idle, ~ 64 x 10mA = 640mA!!!!
WiFi 40mA idle, ~250mA (typical) transmitting

Total = 68mA idle -> 1A max

Almost certainly pushing the limit (I did test it once on an UNO R3 and it was about 550mA before the onboard regulator shut down through thermal overload - there's not enough heatsinking on the PCB).

Option 1:
Use another LM7805 voltage regulator off the 9v switched Vin to provide a second 5v rail at 1A. This will be dissipating about 4W at full load, so will need a small bolt-on heatsink with a thermal resistance of 20degC/Watt or less.

Option 2: (recommended)
Use a small DC-DC converter off the 9v switched Vin to give a second 5v rail at 1A or more. Be sure to test it and set the output to 5v BEFORE wiring it in! Or buy one with fixed output using the same LM2569 chip (other common chips don't have high enough current output).

PS: Colour-coding light colours on white background makes schematic hard to read... & colour-coding 9v and 5v with the same colour is 'dangerous'.
 

Reloadron

Joined Jan 15, 2015
5,667
  • 5V: This is a regulated output from the on board voltage regulator. This power will come from either the USB or DC input jack. This is fed into the on board 5V voltage regulator. The output from the regulator is connected to this pin. You use this pin to provide 5V to power components connected to the Arduino board. The maximum current draw is approx 400mA on usb and higher if using the DC power jack.
This really depends on what you read and I agree with dl324:
The voltage regulator says it can handle over 1A and has self protection. But the problem with that is that the Arduino may not run if it starts shutting down.

Your best bet is to design your other circuitry to operate from whatever voltage you're using to power the Arduino; or calculate the maximum all of the extra circuitry will draw and convince yourself that the Arduino regulator can handle the load.
The Arduino Uno board regulator is a 1.0 amp regulator but I would not count on getting an amp out of it. Also, the problem with using a 9.0 volt standard battery or commonly called PP3 battery is they don't last long in most applications, even the premium alkaline brands. So depending on your needs you may want to rethink the battery choice.

Below is what the power looks like on an Arduino Uno board, you can see where the 5V is derived right off the regulator.
Arduino UNO5V Reg.png

Ron
 

SamR

Joined Mar 19, 2019
2,812
The Arduino I/O pins load is maxed at 200mA although the regulated 5V load can be higher. As others have advised, calculate your loads, both for total connected to I/O pins and separately those simply powered from the regulator. One way to reduce the I/O load is by using switching transistors. It takes less power to switch a transistor than it does to power a higher load. Especially if you use a TO-92 logic-level Mosfet such as the 2N7000.
 

Thread Starter

Miquel19

Joined Aug 16, 2020
37
Do you know (or can measure) the total current required at 5V? That's the first thing to sort out.
This may help: https://forum.arduino.cc/index.php?topic=50287.0
I have done an approximate calculus of the current and I have found:
  1. Esp8266 12-F: 500mA at maximum
  2. 8x8 led matrix: I bought it on amazon to the Az delivery. They say that the matrix consumes at a maximum 160mA (i suppose its real, but I don0t know it for sure)
  3. DFPlayer mini: I have searched and I found that it consumes 25mA
  4. Speaker: my speaker has a power fo 4whatt. So if I make it operate at 5V, P=VI I=P/V I=4/5=0.8A=800mA
 

Thread Starter

Miquel19

Joined Aug 16, 2020
37
The voltage regulator says it can handle over 1A and has self protection. But the problem with that is that the Arduino may not run if it starts shutting down.

Your best bet is to design your other circuitry to operate from whatever voltage you're using to power the Arduino; or calculate the maximum all of the extra circuitry will draw and convince yourself that the Arduino regulator can handle the load.
You are saying that maybe I should for example take another wire from the battery and connect ti to a converter to 5V to then use it to supply power without using the Arduino?
 

AlbertHall

Joined Jun 4, 2014
10,576
I have done an approximate calculus of the current and I have found:
  1. Esp8266 12-F: 500mA at maximum
  2. 8x8 led matrix: I bought it on amazon to the Az delivery. They say that the matrix consumes at a maximum 160mA (i suppose its real, but I don0t know it for sure)
  3. DFPlayer mini: I have searched and I found that it consumes 25mA
  4. Speaker: my speaker has a power fo 4whatt. So if I make it operate at 5V, P=VI I=P/V I=4/5=0.8A=800mA
So you will need a separate 5V supply capable of at least 1.5A running from the 9V input.
 

Thread Starter

Miquel19

Joined Aug 16, 2020
37
As AH said, measure it under worst-case conditions - full volume, all LED on, wifi transmitting.

At a rough estimate
DFplayer 20mA idle, @ 1.5W output ~100mA
LED Matrix 8mA idle, ~ 64 x 10mA = 640mA!!!!
WiFi 40mA idle, ~250mA (typical) transmitting

Total = 68mA idle -> 1A max

Almost certainly pushing the limit (I did test it once on an UNO R3 and it was about 550mA before the onboard regulator shut down through thermal overload - there's not enough heatsinking on the PCB).

Option 1:
Use another LM7805 voltage regulator off the 9v switched Vin to provide a second 5v rail at 1A. This will be dissipating about 4W at full load, so will need a small bolt-on heatsink with a thermal resistance of 20degC/Watt or less.

Option 2: (recommended)
Use a small DC-DC converter off the 9v switched Vin to give a second 5v rail at 1A or more. Be sure to test it and set the output to 5v BEFORE wiring it in! Or buy one with fixed output using the same LM2569 chip (other common chips don't have high enough current output).

PS: Colour-coding light colours on white background makes schematic hard to read... & colour-coding 9v and 5v with the same colour is 'dangerous'.
Yeah, I have found this:
  1. Esp8266 12-F: 500mA at maximum
  2. 8x8 led matrix: I bought it on amazon to the Az delivery. They say that the matrix consumes at a maximum 160mA (i suppose its real, but I don0t know it for sure)
  3. DFPlayer mini: I have searched and I found that it consumes 25mA
  4. Speaker: my speaker has a power fo 4whatt. So if I make it operate at 5V, P=VI I=P/V I=4/5=0.8A=800mA

I like your second idea. You recommended me making another 5V rain to supply the modules? But then I would need to have connected the module to the Arduino ground and battery ground?

And sorry for the schematic, It was the first I did, so I didn't have many considerations like that. Many thanks for that advises, I will fix it to make the schematic better.
 

Irving

Joined Jan 30, 2016
1,070
Yeah, I have found this:
  1. Esp8266 12-F: 500mA at maximum
  2. 8x8 led matrix: I bought it on amazon to the Az delivery. They say that the matrix consumes at a maximum 160mA (i suppose its real, but I don0t know it for sure)
  3. DFPlayer mini: I have searched and I found that it consumes 25mA
  4. Speaker: my speaker has a power fo 4whatt. So if I make it operate at 5V, P=VI I=P/V I=4/5=0.8A=800mA
Some of your figures are unnecessarily high:

Wemos D1 never uses that much unless all GPIO outputs are high and sourcing full load while transmitting at full output power, etc. That's not a real-world scenario.

Your speaker is passive, 4W is its power limit. It's the DFPlayer that is the active component - it drives the speaker. Its power output isn't specified fully but its says "drive speaker less than 3W" so I take 3W as being max output and that as peak music power output (PMPO) so I estimated 1.5W as a typical max power out. Since you have a 5v supply that's a maximum of 2.5v peak and since P = V x I then I = P/V = 1.5/2.5 = 0.6A. Also, from ohm's law, that represents a 4 ohm speaker. (V/I = R, so 2.5/0.6 = 4ohm). That's peak current, the average will be much less so I suggested 100mA - but, as the DFPlayer datasheet suggests, you'll need a big capacitor, say 2200uF, across the Vcc and GND terminals of the DFPlayer to provide a local peak current reservoir.

However, your figure for the matrix seems very low, but its possible. According to the driver chip datasheet, 8 LEDS are lit at any one time with a max of 40mA = 320mA. Do you have a link to the actual product datasheet?
 

Irving

Joined Jan 30, 2016
1,070
I like your second idea. You recommended me making another 5V rain to supply the modules? But then I would need to have connected the module to the Arduino ground and battery ground?
Yes, the module has IN+,IN- and OUT+,OUT- terminals. IN- and OUT- are connected together in the module and one of them should be connected to your GROUND point. You should have only one ground point in the system to avoid ground loops.

Your wiring around the Wemos D1 is all wrong... you don't pass ground, 5v or 3.3V through the level translator... You take 5v to the WEMOS and use its 3.3v output to feed the LV input on the level translator...
 

SamR

Joined Mar 19, 2019
2,812
Remember that individual pins are limited to supplying 40mA with a total for all pins of 200mA. More than that and something will likely emit its magic smoke.
 

Thread Starter

Miquel19

Joined Aug 16, 2020
37
  • 5V: This is a regulated output from the on board voltage regulator. This power will come from either the USB or DC input jack. This is fed into the on board 5V voltage regulator. The output from the regulator is connected to this pin. You use this pin to provide 5V to power components connected to the Arduino board. The maximum current draw is approx 400mA on usb and higher if using the DC power jack.
This really depends on what you read and I agree with dl324:


The Arduino Uno board regulator is a 1.0 amp regulator but I would not count on getting an amp out of it. Also, the problem with using a 9.0 volt standard battery or commonly called PP3 battery is they don't last long in most applications, even the premium alkaline brands. So depending on your needs you may want to rethink the battery choice.

Below is what the power looks like on an Arduino Uno board, you can see where the 5V is derived right off the regulator.
View attachment 216849

Ron
Hi Ron.
Yeah, I don't wont to kill my Arduino demanding more than 500mA to the 5V pin. I will use another rail to power some module.
I will also buy some lithium-ion batteries for that project. I have seen that are rechargeable and much better than the normal ones.
 

dl324

Joined Mar 30, 2015
11,926
You are saying that maybe I should for example take another wire from the battery and connect ti to a converter to 5V to then use it to supply power without using the Arduino?
Yes, and/or use battery voltage whenever possible so you don't waste as much power in voltage regulators.

What is the voltage tolerance of the components being used? What is the current capacity of the battery you're using (is it a 9V transistor radio battery)? How much runtime do you want?
 

Thread Starter

Miquel19

Joined Aug 16, 2020
37
The Arduino I/O pins load is maxed at 200mA although the regulated 5V load can be higher. As others have advised, calculate your loads, both for total connected to I/O pins and separately those simply powered from the regulator. One way to reduce the I/O load is by using switching transistors. It takes less power to switch a transistor than it does to power a higher load. Especially if you use a TO-92 logic-level Mosfet such as the 2N7000.
I will take a look at the transistors. I have seen something about them, but I have never worked with them.
 

SamR

Joined Mar 19, 2019
2,812
The 2N7000 is an N-channel MOSFET in the TO-92 package that will turn ON with only 2V applied to its gate. When ON it can conduct up to 500mA & 60V for a max of 400 mW load. If more needed then the FQP30N06L N-channel MOSFET in the TO-220 package can turn on at 1V at its gate and conduct 5A & 60V for a max of 79W. Both are readily available and relatively inexpensive components to have when needed. The idea is that the Arduino is the control system, not the powerhouse. The Arduino does not have that many mAs available and they should only be used for the controls. Also, with the loads you say you have your 9V battery will have a very short life. USB can provide ~400-500 mA. More than that you will want to go to a wall wart PS that has more capacity. Not sure exactly what those breadboard power supplies are good for. Have several (they came as freebies) but never liked or used them as there are better solutions readily available.

Edit: When ON the gate on the 2N7000 will draw 1mA, the FQP30N06L 500uA. That is why they are used for logic control of power users. Low turn-on Voltage, fully on @ 3.3V & 5V. Plus extremely low current draw to turn on.
 
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Thread Starter

Miquel19

Joined Aug 16, 2020
37
Yes, the module has IN+,IN- and OUT+,OUT- terminals. IN- and OUT- are connected together in the module and one of them should be connected to your GROUND point. You should have only one ground point in the system to avoid ground loops.

Your wiring around the Wemos D1 is all wrong... you don't pass ground, 5v or 3.3V through the level translator... You take 5v to the WEMOS and use its 3.3v output to feed the LV input on the level translator...
Yes, the module has IN+,IN- and OUT+,OUT- terminals. IN- and OUT- are connected together in the module and one of them should be connected to your GROUND point. You should have only one ground point in the system to avoid ground loops.

Your wiring around the Wemos D1 is all wrong... you don't pass ground, 5v or 3.3V through the level translator... You take 5v to the WEMOS and use its 3.3v output to feed the LV input on the level translator...
Sorry but I don't have the led matrix datasheet. I believe that what they put on amazon was true (I don't know it, but I can't do more). Here there is the link where I bought it (it's amazon Spain) https://www.amazon.es/AZDelivery-MA...599837610&sprefix=matriz+,aps,180&sr=8-5&th=1

I will be careful not doing loops and using only one common ground.

Now I can't test what you said, because my batteries had already finished. I will buy some more and test the capacitors. I will also order a converter to get another 5V wire and test the idea.

I don't know what is wrong with the Wemos d1 mini wiring. I took it from a tutorial and it has always worked well. What should I do to solve it?
 
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