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Higher Amperage Answered

Hello guys,
i need help with one of my projects.I have make an DIY Keyboard with neopixel at any button,it works perfect but i have problem with power.
i have 2 usb from keyboard one for arduino and one for keyboard.if i load #define BRIGHTNESS         20  all is good but if i load #define BRIGHTNESS         80 the usb connection is lost and arduino start to lag.this is amperage problem and the question is if any1 know how i can take that usb output from pc and make it with circuit to higher amperage.



2 years ago

USB is limited to 500ma, USB3 can provide more but in either case it is a bad choice to misuse it as a power supply.

Get some supplies:
1 Molex connector
1 fuse rated just over what your electronics need under full brightness, preferably the SMD type with 12 or better 5V rating (i doubt use automotive fuses ;) )
1 USB port, can be from an extension or a complete seperate one that you can solder on
1 USB plug, preferably something from an old device with some cable on it.

That's how it goes, quick and dirty with fast forward:
Connect the molex connetor to your power supply.
Use black for ground and red for the 5V.
The fuse goes into the 5V line.
The new USB port is connected to 5V (after the fuse) and ground.
The USB plug is connected on it too but only the data lines.
Congratulations, you just created a new USB port with "unlimited" power!
To use it plug the USB cable from the spare you connected to the new port into one of your existing ports.
It provides the data connection while the power comes directly from the supply.
Means you can now power the LED's and keyboard with a single cable ;)


Reply 2 years ago


USB => Unexpected Supply Breakdown when running to many LEDs...