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Power Surge on USB Device

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Newbie level 6
May 3, 2007
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surge current usb device


i connected up my microcontroller board (PIC18F4550) via usb to the PC, then i got this msg "A USB Device has exceeded the power limits of its hub port".

Can anyone help to solve this problem?


solving power surge on usb device

It seems your schematic diagram isnot complete.
anyway, i think you have to remove any large capacitance from power lines, because when USB conection stablished,
high surge current may drawn from USB port.
you can use smaller value insted.
another solution is to use small series resistor through USB (+5V), to limit surge current.

get rid of power surge message

I connected up my microcontroller board (PIC18F4550) via usb to the PC, then i got this msg "A USB Device has exceeded the power limits of its hub port".

Can anyone help to solve this problem?


how to solve power surge in usb

Circuits with microcontroller 'hate' relays ..
Try to bypass SW ..
Connect D1 and D2 directly to 'yellow' Vcc, and see how it goes ..


hotfix power surge on usb

Hi Awiskar,

I think Davood is probably right here, you are getting a surge current due to the large caps charging up on the VCC line. To verify this try changing D2 to a ferrite bead and see if this helps. The ferrite bead would be a better solution than a small value resistor as you will get a smaller DC drop on the VCC line, though this may not be a problem as your PIC will have a wide operating voltage range as long as you are running at low frequencies.

hot fix power surge usb

Thankz guys,
i will try out the ferrite bead.

I did try the removal of SW but i still get the same message with the addition of a new messaage saying the device malfunction.

power surge on hub port no device enumeration

As I too had the problem and was searching for a solution I found the information below, however All I did was to reinstall Service pack to solvel the problem.

See Ya!!!!

Hi all,

At first ,it is a microsoft problem!!(Why I think that? cause if I disconnect everything from USB then restart,it pops up again!!)Nothing wrong with your PC or notebook,I've got the same message "Power surge on hub port"which keeps showing up and gets on my nerves :))I've never had this problem before,it appeared just after I installed SP2 and the rest of ...packs,well solution 1 - uninstall SP2 and you'll be fine,solution 2 reinstall XP then install ONLY SP2 and from on disable any updates...I think this bug is included in some XP hotfix which is installed right after SP2 installation.

My solution:

right click START ,choose properties,choose taskbar then customize ,and select power surge...and select ALWAYS HIDE

this way you get rid of the pop-up message and just don't worry about it :))


usb power surge cicrcuit

The USB protocol states that when you plug in a device, it must not draw more than 100mA.
Then, during enumeration, the device can request up to 500mA from the port.
You should really have a way of of switching the psu to the rest of the circuit off untill after the request for more current is acknowledged.

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