RetroPie forum home
    • Recent
    • Tags
    • Popular
    • Home
    • Docs
    • Register
    • Login
    Please do not post a support request without first reading and following the advice in https://retropie.org.uk/forum/topic/3/read-this-first

    That God %$#@ Lightning Bolt

    Scheduled Pinned Locked Moved Help and Support
    power supplystupid errorlightningboltundervolt
    43 Posts 13 Posters 18.2k Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • U
      UnrealDuke
      last edited by

      @mitu, Show me a spec sheet that demands at least 5.2 volts for each piece of silicon on that circuit board. Did you even check the current draw ratings that I posted?

      DarksaviorD 1 Reply Last reply Reply Quote 0
      • DarksaviorD
        Darksavior @UnrealDuke
        last edited by Darksavior

        @unrealduke https://www.raspberrypi.org/documentation/hardware/raspberrypi/power/README.md

        The recommendation and the official power supply is 5.1V 2.5A. So buying anything below is a waste of time. Though, 5.1V is the required voltage. Amps can vary but must be at least 2.5A or higher. There is no reason to buy 1amp stuff. I bought the official pi power supply and have no regrets.

        1 Reply Last reply Reply Quote 1
        • U
          UnrealDuke
          last edited by UnrealDuke

          @all Show me a spec sheet that demands at least 5.2 volts for each piece of silicon on that circuit board.

          Honestly, this thing was is supposed to be USB powered. I probably have the exact same quad-core CPU in my cellphone running off of a 3.8 volt Lithium-Ion battery.

          rbakerR 1 Reply Last reply Reply Quote 0
          • rbakerR
            rbaker @UnrealDuke
            last edited by rbaker

            @unrealduke This link has all you need with regard to current draw . Can't believe you are randomly trying "chargers". Chargers will never work because they are designed to charge - most cannot cope with maintaining a stable voltage under load.

            You then say "The 1 USB power supply(blackweb) that was rated at 4.8 Amps(I would not recommend this) is a mains plug with 2 USB power outlets. Using a "USB Doctor" and seeing the voltage at 4.8 and the current draw from 230-300 MilliAmps." Now are you talking 4.8 amps? or 4.8volts? you appear confused and are mixing the two.

            You need a power supply capable of holding a constant 5.1V at greater than or equal to 2.5A. You will never see the lightning bolt anymore.

            U 1 Reply Last reply Reply Quote 2
            • U
              UnrealDuke @rbaker
              last edited by UnrealDuke

              @rbaker,
              "Now are you talking 4.8 amps? or 4.8volts? you appear confused and are mixing the two."
              Kinda BOTH! The power supply is rated at 4.8 Amps and while in use with the RPi the voltage was at 4.8 Volts and drawing 230-300 MilliAmps.
              alt text
              We are talking about USB standards. Here's a link. https://en.wikipedia.org/wiki/USB#Power_related_specifications
              I should be easily able to power the RPi with at least 4.75 Volts without trouble. The "Designers" of it should have used a different power connector.

              DarksaviorD 1 Reply Last reply Reply Quote 0
              • DarksaviorD
                Darksavior @UnrealDuke
                last edited by Darksavior

                @unrealduke As it was already mentioned by @rbaker , that is a charger. It's not good enough for the pi. The problem here is user error. Chargers can't constantly output that power. You need to purchase a 5.1v 2.5A or higher POWER SUPPLY. It's easier to know what you're getting if the packaging says it's meant for the pi.

                U 1 Reply Last reply Reply Quote 0
                • U
                  UnrealDuke @Darksavior
                  last edited by UnrealDuke

                  @darksavior, Then we are talking about a type C connector that will handle the amperage above the 1.5 Amps. but maintain the 5(5.1+) Volts... USB Standard Voltage is at 5 Volts with 5% Tolerance. 4.8 Volts is within spec. Why even bother to use a Micro B USB connector in the first place if it is supposed to draw more? I am not the one who should answer that one. RPi's are designed to use USB power.

                  rbakerR 3 Replies Last reply Reply Quote 0
                  • rbakerR
                    rbaker @UnrealDuke
                    last edited by

                    @unrealduke said in That God %$#@ Lightning Bolt:

                    RPi's are designed to use USB power

                    Not true, they are designed to use a micro USB connector to receive power!

                    I should be easily able to power the RPi with at least 4.75 Volts without trouble

                    Why do you think this?, it is just not true, especially if you are using a charger. It may boot but when you try to draw current from that, the voltage collapses and so does your Pi. A power supply is regulated - this is a very important concept to understand. In my cabinet builds, I use boxed regulated power supplies similar to those found in PCs but smaller. With those, you can power all sorts of other stuff together with your Pi. RGB LEDs for example. Then there is the whole USB cabling issue - choose a poor one and it will fail to deliver the required power even WITH the correct specifications.

                    1 Reply Last reply Reply Quote 1
                    • rbakerR
                      rbaker @UnrealDuke
                      last edited by

                      @unrealduke Take a look at this for an example. You can wire these up to a build with your own wire and they are rock solid. That said, I have no issues with the official PSU with an Ipac, keyboard and two controllers connected at once with an LED Marquee. I have had issues with a dedicated usb power supply rated at 3A. Each socket was not capable of delivering the minimum spec. It's obvious use would be to charge three things at once like a headset, a phone and a camera. I think this is the issue you are facing. A typical USB 2 port will source a maximum of 500mA and a USB 3 port around 900mA. Some dedicated charging ports source about 1.5A which gives a false sense of security as your hardware appears to work until you stress it. All are inadequate regardless of the rated voltage.

                      1 Reply Last reply Reply Quote 0
                      • rbakerR
                        rbaker @UnrealDuke
                        last edited by

                        @unrealduke Finally, there is a script that I saw on here quite a while ago. It disables the power restrictions. I have not tested it and when disabling things like this, you should be cautious as these are in place to preserve your pi over time. Anyway, you can take a look here.

                        1 Reply Last reply Reply Quote 1
                        • CapemanC
                          Capeman
                          last edited by Capeman

                          If you know anything about building electronic circuits you'll know that there are hundreds of difference schematics of varying quality for any given task.

                          You can make a 5v power supply from 2 diodes, an LM317 with 2 electrolytic caps, 3 resistors, a potentiometer and a breadboard... or you can make a 5v power supply from a 4 diode bridge rectifier, noise reducing ceramic caps in parallel with electrolytic filter caps, dropout and linear voltage regulator ICs and a host of other components.

                          Both will show 5v on the output rails when you connect a multimeter, but the cheaper supply may have voltage drops and spikes ranging in the milli to nano second range, signal noise or a host of other problems.

                          When you get a cheap supply (aka charger), it's cheap for a reason, the builders cut corners and did the bare minimum to get the "required" output into spec . Phone chargers do not need to hold consistent cc/cv since batteries have wide voltage tolerance, sensitive electronics relying on clean power and cv will not fare so well.

                          The only way to accurately check the quality of a power supply is to connect it to the pi, power it up and check the test pads (+pp7, -pp6 on a pi 3) on the bottom of the pi with a scope and view the spikes and dips in voltage when the pi draws a load. A multimeter is too slow to show voltage differences in the milli/nano second ranges, but a decent scope will show you just how crappy that mystery wall wart from Goodwill really is.

                          To put it simply, you get what you pay for.

                          Vector Artist, Designer and Maker of Stuff: Laser Cut Atari / Pixel Theme Bartop

                          1 Reply Last reply Reply Quote 2
                          • U
                            UnrealDuke
                            last edited by

                            Let's see how cheap these things really are...
                            alt text
                            Interesting enough they are rated at 5 volts.

                            CapemanC DougAD 2 Replies Last reply Reply Quote -1
                            • CapemanC
                              Capeman @UnrealDuke
                              last edited by

                              @unrealduke Canakit are decent supplies. If youre getting a lightning bolt from a those, then theres something wrong with your setup. Too many connections to the GPIO, power hungry usb adapters or just a bad pi board.

                              Vector Artist, Designer and Maker of Stuff: Laser Cut Atari / Pixel Theme Bartop

                              quicksilverQ 1 Reply Last reply Reply Quote 0
                              • DougAD
                                DougA @UnrealDuke
                                last edited by

                                @unrealduke i haven’t seen any problems with my Canakit PSU, admittedly it only drives a Pi and a zero delay joystick interface with illuminated buttons.

                                1 Reply Last reply Reply Quote 0
                                • quicksilverQ
                                  quicksilver @Capeman
                                  last edited by

                                  @capeman my canakit gives me the occasional lighting bolt on my overclocked pi3. I have heard others say the same. I switched to a different power supply and no longer have issues.

                                  1 Reply Last reply Reply Quote 0
                                  • U
                                    UnrealDuke
                                    last edited by

                                    I had no intention of overclocking my RPi. Just the idea of using a regular USB power supply that is commonly available to power it. Since I have two RPi's I bought 2 proper power supplies which hopefully will never give me a "Lightning Bolt" ever again. Unfortunately I had to wait until the guy who sold the things opened his store. Frequently he had a sign in the door that said "Back in 1 Hour".

                                    1 Reply Last reply Reply Quote 0
                                    • ClassicGMRC
                                      ClassicGMR @quicksilver
                                      last edited by

                                      @quicksilver said in That God %$#@ Lightning Bolt:

                                      @classicgmr https://www.amazon.com/Mackertop-HSTNN-LA43-PA-1150-22HA-779573-001-761247-002/dp/B01HB44IE6

                                      This is the power supply that I'm using with my pi3, I am also using the super kintaro case. I have had no issues with this power supply and I'm overclocked.

                                      Just an update to reclaim my thread. ;)

                                      This has been working just fine for me. Haven't seen a lightning bolt since I started using it. Only hardwired 3A cables for me from now on. Thank you all for your suggestions. :)

                                      Growing older is mandatory. Growing up is optional!
                                      Enjoy the ride!

                                      1 Reply Last reply Reply Quote 0
                                      • First post
                                        Last post

                                      Contributions to the project are always appreciated, so if you would like to support us with a donation you can do so here.

                                      Hosting provided by Mythic-Beasts. See the Hosting Information page for more information.