[time-nuts] newbie question Thunderbolt supply
Ed Palmer
ed_palmer at sasktel.net
Mon Aug 27 16:35:16 UTC 2012
There are thermal pads that are thermally conductive. You typically see
them in laptops and, oddly, optical drives. They're usually one or two
mm thick and very soft and squishy. Pull the bottom plate off any
full-size optical drive and you'll probably find one or two pieces. I
see lots of them on the auction site, but I have no personal experience
with those. It looks like there's at least one or two that are
available in large pieces and I saw thicknesses from 0.4mm up to 4.0mm.
I wouldn't expect these to move heat nearly as well as a thin layer of
thermal grease (which is itself a thermal insulator), but for some
applications it works and is the only practical solution.
Ed
On 8/27/2012 10:12 AM, Bob Camp wrote:
> Hi
>
> The pad stuff is normally an insulator. It's not very stable, so there may
> be better alternatives.
>
> Bob
>
> -----Original Message-----
> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
> Behalf Of EWKehren at aol.com
> Sent: Monday, August 27, 2012 10:44 AM
> To: time-nuts at febo.com
> Subject: Re: [time-nuts] newbie question Thunderbolt supply
>
> There are components and traces.
> Bert
>
>
> In a message dated 8/27/2012 10:10:45 A.M. Eastern Daylight Time,
> jsternmd at att.net writes:
>
> Are these thermal pads temp conductive or insulative? If you want heat
> dissipation why not use the readily available thermal grease used for
> semiconductor mounting? Cheap and not really messy if applied correctly
>
> jerry
>
> -----Original Message-----
> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
> Behalf Of EWKehren at aol.com
> Sent: Monday, August 27, 2012 9:38 AM
> To: time-nuts at febo.com
> Subject: Re: [time-nuts] newbie question Thunderbolt supply
>
> Thank you. Will look for it here under thermal pad.
> Bert
>
>
> In a message dated 8/27/2012 8:08:30 A.M. Eastern Daylight Time,
> azelio.boriani at screen.it writes:
>
> Here in Europe Farnell has the 3M thermal pad in sheets (105x150mm)...
>
> On Mon, Aug 27, 2012 at 12:48 PM, ew <ewkehren at aol.com> wrote:
>
>> Chris
>> Starting with 3.4 W used by the Tbolt my battery version burns 4.4 W.
>> Using a switcher do generate 7 V 4.8 W and running the 7805 directly
>> from 14.5 V 6.2.W. I use like you an IC temp sensor, two stage op amp
>> driving a fan holding the backplate temp constant and total power
>> goes up to 7.6 W since the oven has to work harder. T bolt, switchers
>> and all regulators are on the other side of the 3/32" Alu plate. The
>> AC switcher
> is
>> not included in the power numbers. but is also on the plate. Plate is
> held
>> at 40 C.
>> I am looking for a way to more closely couple the Tbolt circuit board
>> to the back plate and am looking for the material switchers use
>> between semiconductor and cooling plate Any one know where I can buy
>> it in sheet form?
>> Bert Kehren
>>
>>
>>
>>
>> -----Original Message-----
>> From: Chris Albertson <albertson.chris at gmail.com>
>> To: Discussion of precise time and frequency measurement <
>> time-nuts at febo.com>
>> Sent: Sun, Aug 26, 2012 12:31 pm
>> Subject: Re: [time-nuts] newbie question Thunderbolt supply
>>
>>
>> On Sun, Aug 26, 2012 at 3:46 AM, <EWKehren at aol.com> wrote:
>>> Having played with several solutions I found the best is a 12 V 1 A
>> switcher with the output voltage increased to 15 V, check the
>> capacitors and if necessary replace with 25 V. I laid out a PC
>> board that has a TC7662A inverter followed by a 79L12. Also on the
>> board is a 7812 followed by
> a
>> 7805.
>> Putting them in series gives me good thermal distribution. ....
>>
>> ne of the advantages of generating waste heat like that is that you
>> can ut the heat to good use. I build a temperature controlled fan.
>> It is ery simple a temperature sensor IC connects to an opamp that
>> drives a ower transistor that drives a 12V fan.
>> As for the power supply. I used a filter that does not drop any
>> volts
> and
>> can't see any RF on the DC using my old 365 Tek scope or by using a
> more
>> ensitive RF power meter.
>>
>> hris Albertson
>> edondo Beach, California
>> ______________________________________________
>> ime-nuts mailing list -- time-nuts at febo.com o unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> nd follow the instructions there.
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
More information about the time-nuts
mailing list