Can USB thumb drives be air cooled?

I use mine a lot and they heat up quite a bit in the hot weather

Peter Jason wrote:

> I use mine a lot and they heat up quite a bit in the hot weather

USB thumb drive = USB-connected flash drive (solid-state storage device)

Flash is memory. Why is yours getting so hot?

Max current through USB port: 1/2A
Voltage from USB port: 5V

That means max power consumption for any USB-powered device, like a
thumb drive, is . From the CiteSeer article on USB drives at
http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf,
the worse case for power consumption in Figure 1 is SanDisk 4GB at close
to 80mA. Well, with 5V for source voltage from the USB port, that's a
mere 0.4W but a hefty portion is for the large bright LED indicator.

Remember that without the LED indicator and with a different layout,
these same flash devices are used as memory cards that slide into
digital cameras where the card is totally encased and there is no air
circulation. Power consumption is so low that it's rare to find it
mentioned in the maker's specs for their products. That's because they
don't expect the product to be under continual use (i.e., constant use
with no rest phase). Despite Microsoft adding ReadyBoost to Windows
Vista+ (a dumb decision since oxide stress and consumption of reserve
space for masking bad sectors will eventually make a flash drive
catastrophically fail which means data corruption from loss of memory),
it is expected that you occasionally use the flash drive. Although
power consumption is low, continual use can drive up the temperature.

http://blog.premiumusb.com/2011/02/w...drive-get-hot/
http://blog.premiumusb.com/2011/03/h...ash-drive-get/

Can USB thumb drives be air cooled? Yes, they always are. They are
designed for convection cooling using the air around the device. Maybe
you meant to increase air movement beyond normal convection by using a
fan to up the air flow rate around the device. You can always point a
fan at any device that is generating heat to blow cooler air over it and
improve the convection rate.

Here ya go:
http://www.tradeeasy.com/supplier/16...table-fan.html
http://www.google.com/search?tbm=isch&q=%2Busb+%2Bfan

Peter Jason wrote:
> I use mine a lot and they heat up quite a bit in the hot weather

If you're concerned about it, you can arrange a cooling fan
next to the item.

I have a couple external fans now. One points at my rack
of AC wall wart power adapters. A second cooling fan points
at my ADSL modem (draws perhaps 10 watts). The wall warts
shouldn't need cooling, but I added it as a debugging step
when I started having problems. On the ADSL modem, it was
a suggestion based on failures in the caps inside that model.
I added the fan to see if the thing would last longer.

You can buy 12V adapters at an electronics store, buy a computer
case cooling fan, then wire them together.

"12VDC wall adapter - switchable voltage, two pin Adaptaplug interface $20.49"

http://www.radioshack.com/product/in...ductId=3875403

"Adaptaplug to tinned wires adapter $5"

http://www.radioshack.com/product/in...ductId=3870008

When using stuff like that, it's up to you to figure out which
wire is (+) and which wire is (-). [Use a multimeter...]
On a two wire fan, red is the (+) one and black is the (-) one.
Connect (+) to (+) etc.

You can cut the Molex off of one of these, then twist together
the load to the source.

http://www.radioshack.com/product/in...ductId=2262091

To make a stand for the fan, buy some 3" bolts and nuts. By putting
the bolts through two of the fan holes, you can make a stand for the fan
to keep it upright. Placing a piece of rubber underneath the thing,
will also reduce the coupling of fan motor hum into the desk.

The fan can still get tipped over of course. My scheme isn't bulletproof.

To cover where the wires get twisted together, you can use heat
shrink (polyolefin) tubing. Cut off a 1" length, fish it over
the wire on one item, before twisting the wires together. Slide
the tubing over the wire to cover it. Apply gentle heat (that's the
hard part, too much heat and you'll burn it). Heat shrink, if done
well, can be a bit more reliable protection than electrical tape.
In warm weather, electrical tape becomes gummy. The mistake
I make all the time, is selecting a too slim piece of tubing.
It has to be a bit larger than the thing you're covering, or
it won't easily slide over top of it.

http://www.radioshack.com/product/in...ductId=2102875

You can connect more than one fan (in parallel) to the adapter.
If a fan draws 350mA and you bought a 1 amp adapter, you
could connect two fans to it (twist the three (+) together etc).

Paul

"Peter Jason" <pj@jostle.com> wrote in message
news:3tbci75vile1kmu612ac3f2ju670bvlue9@4ax.com...

>I use mine a lot and they heat up quite a bit in the hot weather

Some manufacturers e.g. NetGear make USB devices
with air-cooling ports across the middle.

--
Don Phillipson
Carlsbad Springs
(Ottawa, Canada)

On 1/30/2012 12:51 AM, Peter Jason wrote:
> I use mine a lot and they heat up quite a bit in the hot weather

It _IS_ air cooled, unless you have a liquid cooled one and those are
pretty rare. Seriously though, with a maximum legal power dissipation of
2.5W even the worst-designed unit should never get warm enough to cause any
problems. If yours is failing due to heat (and how would you know?) then a
new drive might be a better solution.

On Mon, 30 Jan 2012 03:04:20 -0600, VanguardLH <V@nguard.LH> wrote:

>Peter Jason wrote:
>
>> I use mine a lot and they heat up quite a bit in the hot weather
>
>USB thumb drive = USB-connected flash drive (solid-state storage device)
>
>Flash is memory. Why is yours getting so hot?
>
>Max current through USB port: 1/2A
>Voltage from USB port: 5V
>
>That means max power consumption for any USB-powered device, like a
>thumb drive, is . From the CiteSeer article on USB drives at
>http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf,
>the worse case for power consumption in Figure 1 is SanDisk 4GB at close
>to 80mA. Well, with 5V for source voltage from the USB port, that's a
>mere 0.4W but a hefty portion is for the large bright LED indicator.
>
>Remember that without the LED indicator and with a different layout,
>these same flash devices are used as memory cards that slide into
>digital cameras where the card is totally encased and there is no air
>circulation. Power consumption is so low that it's rare to find it
>mentioned in the maker's specs for their products. That's because they
>don't expect the product to be under continual use (i.e., constant use
>with no rest phase). Despite Microsoft adding ReadyBoost to Windows
>Vista+ (a dumb decision since oxide stress and consumption of reserve
>space for masking bad sectors will eventually make a flash drive
>catastrophically fail which means data corruption from loss of memory),
>it is expected that you occasionally use the flash drive. Although
>power consumption is low, continual use can drive up the temperature.
>
>http://blog.premiumusb.com/2011/02/w...drive-get-hot/
>http://blog.premiumusb.com/2011/03/h...ash-drive-get/
>
>Can USB thumb drives be air cooled? Yes, they always are. They are
>designed for convection cooling using the air around the device. Maybe
>you meant to increase air movement beyond normal convection by using a
>fan to up the air flow rate around the device. You can always point a
>fan at any device that is generating heat to blow cooler air over it and
>improve the convection rate.
>
>Here ya go:
>http://www.tradeeasy.com/supplier/16...table-fan.html
>http://www.google.com/search?tbm=isch&q=%2Busb+%2Bfan

Will wonders never cease? Instead of buying one of these gizmos I'll
set up a hub just before or after one of the HDD fans so that this
will do the job. Also, I notice some thumb drives produce less heat
than others.

On Mon, 30 Jan 2012 04:48:10 -0500, Paul <nospam@needed.com> wrote:

>Peter Jason wrote:
>> I use mine a lot and they heat up quite a bit in the hot weather
>
>If you're concerned about it, you can arrange a cooling fan
>next to the item.
>
>I have a couple external fans now. One points at my rack
>of AC wall wart power adapters. A second cooling fan points
>at my ADSL modem (draws perhaps 10 watts). The wall warts
>shouldn't need cooling, but I added it as a debugging step
>when I started having problems. On the ADSL modem, it was
>a suggestion based on failures in the caps inside that model.
>I added the fan to see if the thing would last longer.
>
>You can buy 12V adapters at an electronics store, buy a computer
>case cooling fan, then wire them together.
>
>"12VDC wall adapter - switchable voltage, two pin Adaptaplug interface $20.49"
>
>http://www.radioshack.com/product/in...ductId=3875403
>
>"Adaptaplug to tinned wires adapter $5"
>
>http://www.radioshack.com/product/in...ductId=3870008
>
>When using stuff like that, it's up to you to figure out which
>wire is (+) and which wire is (-). [Use a multimeter...]
>On a two wire fan, red is the (+) one and black is the (-) one.
>Connect (+) to (+) etc.
>
>You can cut the Molex off of one of these, then twist together
>the load to the source.
>
>http://www.radioshack.com/product/in...ductId=2262091
>
>To make a stand for the fan, buy some 3" bolts and nuts. By putting
>the bolts through two of the fan holes, you can make a stand for the fan
>to keep it upright. Placing a piece of rubber underneath the thing,
>will also reduce the coupling of fan motor hum into the desk.
>
>The fan can still get tipped over of course. My scheme isn't bulletproof.
>
>To cover where the wires get twisted together, you can use heat
>shrink (polyolefin) tubing. Cut off a 1" length, fish it over
>the wire on one item, before twisting the wires together. Slide
>the tubing over the wire to cover it. Apply gentle heat (that's the
>hard part, too much heat and you'll burn it). Heat shrink, if done
>well, can be a bit more reliable protection than electrical tape.
>In warm weather, electrical tape becomes gummy. The mistake
>I make all the time, is selecting a too slim piece of tubing.
>It has to be a bit larger than the thing you're covering, or
>it won't easily slide over top of it.
>
>http://www.radioshack.com/product/in...ductId=2102875
>
>You can connect more than one fan (in parallel) to the adapter.
>If a fan draws 350mA and you bought a 1 amp adapter, you
>could connect two fans to it (twist the three (+) together etc).
>
> Paul

Thanks, but since I have a bank of large fans cooling the HDDs I'll
set up a bracket just before one of these so that the inrush of air
can cool the thumb drive as well. The maker of the case sells hubs I
can adapt for this purpose and all the fans work rather well.
http://imageshack.us/photo/my-images...gp3303red.jpg/

Peter Jason wrote:

>
> Thanks, but since I have a bank of large fans cooling the HDDs I'll
> set up a bracket just before one of these so that the inrush of air
> can cool the thumb drive as well. The maker of the case sells hubs I
> can adapt for this purpose and all the fans work rather well.
> http://imageshack.us/photo/my-images...gp3303red.jpg/

Yeah, I was just pointing out, that if you need cooling outside the
computer, for other gear, there are ways to do it.

As far as the flash chips themselves go, I couldn't find any advice
on whether heat has an adverse affect on storage life of flash.

Paul