A 300-Watt USB plug?

In comp.sys.ibm.pc.hardware.chips daytripper wrote in part:
Actually, wallwarts *are* dirt cheap.

As Keith posts side-thread, not all that cheap, especially if you
are targetting a device which retails for $99. Then there is all
the packaging hassle and different versions required, especially
for the EU states. Not to mention RMA issues.


But, more to the point, when have you ever even heard of a
"300 watt wallwart"? Or anything even close to that capacity?

Granted no, but I'd include power bricks in "wallwarts", and many
of them are ~100W, admittedly for heavier devices like laptops.


I'd guess 99.very_large_integer% of the wallwarts *ever sold* -
at least in the Reality I inhabit - are under 24 watts capacity...

Agreed. A less ambitious goal for PoUSB would be more reasonable.
The current 500mA @ 5V is 'way light. It is rather silly that
2.5"HDs can be USB powered, but 3.5"HDs need an external source.
Why the stupid wallwart for speakers? 24W is quite reasonable.

The idea of powering a laser printer through the CPU is just
nuts. An inkjet, OK. I'm a little squeamish about centrally
powering the monitor even though my first machines worked this way.
But not a projector (that bulb needs cooling).

-- Robert

On Sat, 9 Oct 2010 22:19:28 +0000 (UTC), Robert Redelmeier
wrote:

In comp.sys.ibm.pc.hardware.chips daytripper wrote in part:
Actually, wallwarts *are* dirt cheap.

As Keith posts side-thread, not all that cheap, especially if you
are targetting a device which retails for $99. Then there is all
the packaging hassle and different versions required, especially
for the EU states. Not to mention RMA issues.

Two points. Our (10W) wall warts have replaceable connectors for world-wide
use. That can be dealt with. Some devices are in the $50 range. 10% of
*retail* to the WW manufacturer is a *lot*.

But, more to the point, when have you ever even heard of a
"300 watt wallwart"? Or anything even close to that capacity?

Granted no, but I'd include power bricks in "wallwarts", and many
of them are ~100W, admittedly for heavier devices like laptops.

Laptops powered by USB... Now there is a picture. ;-) Who's the boss?

I'd guess 99.very_large_integer% of the wallwarts *ever sold* -
at least in the Reality I inhabit - are under 24 watts capacity...

Agreed. A less ambitious goal for PoUSB would be more reasonable.
The current 500mA @ 5V is 'way light. It is rather silly that
2.5"HDs can be USB powered, but 3.5"HDs need an external source.
Why the stupid wallwart for speakers? 24W is quite reasonable.

Some 2.5" drives needed a PS, too. Or perhaps it's just that not all USB
ports really can supply .5A. Anyway, some of mine came with WWs.

The idea of powering a laser printer through the CPU is just
nuts. An inkjet, OK. I'm a little squeamish about centrally
powering the monitor even though my first machines worked this way.
But not a projector (that bulb needs cooling).

SMOP for the device driver. ;-)

On 10/09/10 06:19 pm, Robert Redelmeier wrote:

snip

The current 500mA @ 5V is 'way light. It is rather silly that
2.5"HDs can be USB powered, but 3.5"HDs need an external source.

Don't 3,5" HDs need 12v as well as 5v?

Perce

In comp.sys.ibm.pc.hardware.chips Percival P. Cassidy wrote in part:
On 10/09/10 06:19 pm, Robert Redelmeier wrote:
The current 500mA @ 5V is 'way light. It is rather silly that
2.5"HDs can be USB powered, but 3.5"HDs need an external source.

Don't 3,5" HDs need 12v as well as 5v?


Good point, but with enough current allowable on the 5v,
the 12v could be made by switching up. There are good
tech reasons, but it just exaggerates a category break.

-- Robert

In comp.sys.ibm.pc.hardware.storage Percival P. Cassidy wrote:
On 10/09/10 06:19 pm, Robert Redelmeier wrote:

snip

The current 500mA @ 5V is 'way light. It is rather silly that
2.5"HDs can be USB powered, but 3.5"HDs need an external source.

Don't 3,5" HDs need 12v as well as 5v?

They do and the reason is far heavier spindle and head assembly.

Arno
--
Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email:
GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F
----
Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans