Western Digital starts selling a 314GB PiDrive
#11
TLLIM


How much current can the board traces handle on the USB side?  Did you engineer a 1.5 or 2X overcurrent design into the board or is the current suppose to to be maintained around the standard 500Ma. Explain a little please,  (USB)  current limit at traces, trace protection, current limiting, etc
  Reply
#12
(03-16-2016, 09:10 PM)DeepBlu Wrote: TLLIM


How much current can the board traces handle on the USB side?  Did you engineer a 1.5 or 2X overcurrent design into the board or is the current suppose to to be maintained around the standard 500Ma. Explain a little please,  (USB)  current limit at traces, trace protection, current limiting, etc

The concern is when USB draw too much current can cause PMIC overload. Directly connect USB power to DC-in resolve such concern but PMIC loss the USB power management capability.
  Reply
#13
TLLIM   So what is the maximum current you recommend that a single USB port can carry, the std 500ma or is the board designed  for something greater?. I see the point where you are given the option to change the current source from either the on board PWM or select (through the jumper) to source from the external DC supply.

Looks like you use 100mil trace in internal pwr config feeding a 150mil trace to USB conn  = This looks like the  500ma USB std.

and

For external pwr current is feed through the 150mil trace which would be about 750ma per USB conn = This is a non std configuration.

Adding the two USB connectors would be about 1.5A max current draw from ext pwr (if configured to external pwr)

Even though you increased trace width for external pwr, to allow an extra 250ma to be available to a single USB conn it
would seem a little more common sense to to just use a powered hub and not stress the board (is not fused in ext pwr conf that I can see),
This is not all inclusive, with a proper pwr supply, good tracking of current draws, lots of things can be done, but all it takes is one brief short on the USB side and the trace may open up.

Also, is there a paticular reason (or application) you had in mind when designing this configuration (the external pwr one) Off loading the USB current perhaps?

Next time consider shooting for a 3A output and protect it with resettable fuses (maybe USB 3 will come down in cost and/or USB-C) for ext pwr. The SBC wars have just begun, I'm sure with all the input folks have been feeding into this forum have given rise to the next idea/approach, might affect cost/size, but nowadays product life is getting a little shorter each cycle.
  Reply
#14
(03-17-2016, 02:10 PM)DeepBlu Wrote: TLLIM   So what is the maximum current you recommend that a single USB port can carry, the std 500ma or is the board designed  for something greater?. I see the point where you are given the option to change the current source from either the on board PWM or select (through the jumper) to source from the external DC supply.

Looks like you use 100mil trace in internal pwr config feeding a 150mil trace to USB conn  = This looks like the  500ma USB std.

and

For external pwr current is feed through the 150mil trace which would be about 750ma per USB conn = This is a non std configuration.

Adding the two USB connectors would be about 1.5A max current draw from ext pwr (if configured to external pwr)

Even though you increased trace width for external pwr, to allow an extra 250ma to be available to a single USB conn it
would seem a little more common sense to to just use a powered hub and not stress the board (is not fused in ext pwr conf that I can see),
This is not all inclusive, with a proper pwr supply, good tracking of current draws, lots of things can be done, but all it takes is one brief short on the USB side and the trace may open up.

Also, is there a paticular reason (or application) you had in mind when designing this configuration (the external pwr one) Off loading the USB current perhaps?

Next time consider shooting for a 3A output and protect it with resettable fuses (maybe USB 3 will come down in cost and/or USB-C) for ext pwr. The SBC wars have just begun, I'm sure with all the input folks have been feeding into this forum have given rise to the next idea/approach, might affect cost/size, but nowadays product life is getting a little shorter each cycle.
The first sentence assumption is correct.

As mentioned, this implementation is reduce PMIC loading when connect to high peak current USB device such as hard disk. The USB current limited (we set at 680mA, slightly more than 500mA) setting still the same on both selection.
  Reply
#15
Hi @tllim

KS Update #17 mentions a partnership between PINE64 and WD. The drive shown there is obviously not the PI drive. Do you have some updates about this partnership?
  Reply
#16
(03-18-2016, 12:11 AM)umiddelb Wrote: Hi @tllim

KS Update #17 mentions a partnership between PINE64 and WD. The drive shown there is obviously not the PI drive. Do you have some updates about this partnership?
It is a large capacity 3TB drive, we will disclose more info when time is right. The one show in KS update#17 is a 1TB version.
  Reply
#17
Id rather have a 256GB usb 3.0 flash drive for the same price since it would be far more versitle.
  Reply
#18
Just verified by an owner of the new 314 PiDrive that it is rated at 5v / 0.55A.
  Reply
#19
(03-18-2016, 07:14 AM)coleshores Wrote: Id rather have a 256GB usb 3.0 flash drive for the same price since it would be far more versitle.

Given the pine64 does not have either USB3 nor ESATA you would need to scale back your hopes.

In terms of space, some people need more space, but might not need it as quick. For example, to keep a copy of my photo and video album on the pine, I would need 700GB. I wouldn't expect flash drives from WD, but nothing says pine64 can't also be working with a flash drive vendor as well. Choice is good.
  Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)