Pi 3 input current too low
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I'm in need of some help with my pi3. I've got retropie installed along with some games and am having issues with major lag on some emulators. I have been doing some research and have found that the pi3 can consume up to 2.5A. The problem that I'm running into, is that it won't consume more than 600mA.
I've got a power supply that can output 2A, and the micro usb cable in using is the same one I've tested with on a phone to verify that amperage. I've also got a usb amp meter to check this usage while using the pi.
I don't have any modifications to the pi, nor have I ever. Brand new unit, fresh install
Thanks for the help.
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@Mazda_Speed_120 you'll need a psu that can do 2.5a minimum for a Pi3 dude
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@Mazda_Speed_120 you need a cord designed for the pi. Cell phone chargers are designed to increase and lower voltage. They communicate with the phone/tablet devices too. Its how they do the fast charging. They dont work right on a pi3.
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@Mazda_Speed_120 said in Pi 3 input current too low:
The problem that I'm running into, is that it won't consume more than 600mA
Some problems with your understanding. The Pi will draw current from your supply as and when it demands it. Your supply needs to be up for the job when these demands are made. Your 2A supply will provide 2A when that demand is made of it. A power supply rating of 2A doesn't mean that it will throw 2A at everything connected to it. Electronic devices would be destroyed if this were the case. When you boot up a Pi, on average, it demands around 300-400mA. Playing video around 500-600mA. The power requirements of the Pi increase as you make use of the various interfaces on the Pi. For example, the Camera Module requires 250mA and keyboards and mice can take as little as 100mA or as much as 1A! My advice for all electronic projects is buy a decent regulated 5A power supply and then you can connect pretty much what you want to your projects. Things like keyboard decoders, rgb lighting, usb disks, the works. You will have spare capacity. Phone chargers are a bad choice for Pi powering. This is because cheap ones are often not regulated properly and some are designed to trickle charge products over time. Once you use them as a power supply, the connected device often demands the full rated power under stress and it will either over heat or explode. This is why I recommend spare capacity on your power supply. Remember it like this...You provide the correct voltage (5V) and the Pi will take whatever current it needs. If your supply is incapable of supplying enough current then the voltage will collapse (and probably overheat your pack), and if it drops too far unpredictable things will happen inside the Pi and the lightning bolt will appear.
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@rbaker I had a similar assumption about the power supplies, so I then switched over to a portable battery pack to check and see if it worked any differently. And I've still had the same experience. I figured many of the wall adaptors can fluctuate, and I don't believe that my battery pack has any current restrictions other than 2A, but I could be mistaken. This is the battery pack that I tried.
https://www.amazon.com/gp/aw/s//ref=mw_dp_a_s?ie=UTF8&k=Talentcell
Please let me know if I should still try another power supply. I've got a bench power supply that I could use to test current flow, I'd just have to hack apart an old USB cable to get it to work. The bench supply can output up to 3A.
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what the pi requires is a stable voltage, the amp rating is how much it can deliver and maintain that voltage. the pi works from 4.75-5.25v, if you draw 1 amp and your voltage drops below 4.75v due to the supply cant keep up your pi will under clock itself to a slower speed to keep ruining and if it cant adjust fast enough it will reboot or lock up. a good 2amp supply will run these things all day long unless you plug in usb devices pulling even more power. I have found samsung cell phone chargers to be grat and anything from walgreens to be junk. Do you see the lightning bolt when playing?
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define "lag"? there are many ways a perfectly powered pi 3 system can "lag".
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@Mazda_Speed_120 I just noticed "lag" too in your first post. I missed it before. You don't need to be swapping in and out supplies if you have one that can deliver 2.5A. The "lag" is probably due to an incorrect setup of a particular emulator or emulator choice or refresh rate issue. What emulator are you using? What rom?
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