[Mr Sandman[_6_]]

Hi peeps,
I have an Onkyo 5009 AV Reciever with the very common problem of overheating HDMI board. You can see it just under the grill for cooling in the case. I have an infrared heat sensitive camera and discovered there are several small ic's that get very hot very quickly- i.e. 70-80c. The ICs are very small, 10mmx10mm up to 10mmx16mm and thereabouts but there is space of about an inch above so room for a heat sink maybe. I could Fit heat sinks to those chips(if there are any small enough) or fit fans above or both. But does anyone have any experience cooling small chips like these?

Cheers

Steve

[Mike Tomlinson]

En el artículo ,
Mr Sandman escribió:

But does anyone have any experience
cooling small chips like these?

Yes. You do need some airflow though, not much.

Google "RAM sinks" or "RAMsinks"

http://www.ebay.com/bhp/ram-heatsink

--
(\_/)
(='.'=) "Between two evils, I always pick
(")_(") the one I never tried before." - Mae West

[[email protected]]

On Wednesday, 26 July 2017 07:43:50 UTC+1, Mr Sandman wrote:
Hi peeps,
I have an Onkyo 5009 AV Reciever with the very common problem of overheating HDMI board. You can see it just under the grill for cooling in the case.. I have an infrared heat sensitive camera and discovered there are several small ic's that get very hot very quickly- i.e. 70-80c. The ICs are very small, 10mmx10mm up to 10mmx16mm and thereabouts but there is space of about an inch above so room for a heat sink maybe. I could Fit heat sinks to those chips(if there are any small enough) or fit fans above or both. But does anyone have any experience cooling small chips like these?

Cheers

Steve

Yes. Either would help. You don't need a lot of tep reduction fro 80C to gain longevity. Sitting a small low speed fan on it is presumably easiest.


NT

[Dave Liquorice[_2_]]

On Tue, 25 Jul 2017 23:43:47 -0700 (PDT), Mr Sandman wrote:

The ICs are very small, 10mmx10mm up to 10mmx16mm and thereabouts but
there is space of about an inch above so room for a heat sink maybe. I
could Fit heat sinks to those chips(if there are any small enough)

There almost certainly is small enough heatsinks, even if you use
those intended for a Raspberry Pi. Attaching them with a decent
thermal joint may be more of an issue. I've stuck small heatsinks
onto the bridge rectifiers in my scope with "BERGQUIST
BP100-0.005-00-1/1 - Thermal Adhesive Tape, Bond-Ply 100, 0.8 W/m.K,
0.005" Farnell order code: 8783721.

Fans really only work if there is a decent hot surface area to
transfer the heat, they are noisey and wear out. I'd find the largest
heatsinks that'll fit and sticke 'em on and then see what the
temperatures are.

--
Cheers
Dave.

[[email protected]]

On Wednesday, 26 July 2017 10:31:02 UTC+1, Dave Liquorice wrote:
On Tue, 25 Jul 2017 23:43:47 -0700 (PDT), Mr Sandman wrote:

The ICs are very small, 10mmx10mm up to 10mmx16mm and thereabouts but
there is space of about an inch above so room for a heat sink maybe. I
could Fit heat sinks to those chips(if there are any small enough)

There almost certainly is small enough heatsinks, even if you use
those intended for a Raspberry Pi.

any flat bit of ali would do as long as it increases surface area significantly. Not much performance is required

Attaching them with a decent
thermal joint may be more of an issue. I've stuck small heatsinks
onto the bridge rectifiers in my scope with "BERGQUIST
BP100-0.005-00-1/1 - Thermal Adhesive Tape, Bond-Ply 100, 0.8 W/m.K,
0.005" Farnell order code: 8783721.

superglue

Fans really only work if there is a decent hot surface area to
transfer the heat,

true if you need a lot of thermal improvement, but this job doesn't

they are noisey

anything from totally silent to noisy

and wear out. I'd find the largest
heatsinks that'll fit and sticke 'em on and then see what the
temperatures are.


NT

[T i m]

On Wed, 26 Jul 2017 10:30:59 +0100 (BST), "Dave Liquorice"
wrote:

On Tue, 25 Jul 2017 23:43:47 -0700 (PDT), Mr Sandman wrote:

The ICs are very small, 10mmx10mm up to 10mmx16mm and thereabouts but
there is space of about an inch above so room for a heat sink maybe. I
could Fit heat sinks to those chips(if there are any small enough)

There almost certainly is small enough heatsinks, even if you use
those intended for a Raspberry Pi. Attaching them with a decent
thermal joint may be more of an issue. I've stuck small heatsinks
onto the bridge rectifiers in my scope with "BERGQUIST
BP100-0.005-00-1/1 - Thermal Adhesive Tape, Bond-Ply 100, 0.8 W/m.K,
0.005" Farnell order code: 8783721.

Or the heatsinks used on the driver chips on my 3D printer (A4988). I
glued mine on with a thermal two part epoxy and they have been fine
ever since.

https://s-media-cache-ak0.pinimg.com...6b6ba8e32c.jpg
http://www.arcticsilver.com/arctic_s...l_adhesive.htm

I found that because they were so small, using thermal tape (or the
tape we used) allowed the heatsinks to move or even get knocked off.
;-(

Because the 'thickness' of the epoxy was mush less than that of the
tape, I sandwiched a brass (reasonable thermal conductivity) washer
the same OD as the size of the chip onto the top of the chip to raise
the heatsink slightly to ensure it didn't touch the surrounding
components.

Fans really only work if there is a decent hot surface area to
transfer the heat, they are noisey and wear out. I'd find the largest
heatsinks that'll fit and sticke 'em on and then see what the
temperatures are.

+1 Ideally etc.

However, because I believe the 3D printer driver IC's actually 'sink'
their heat downwards to the PCB, I fitted a silent fan into the end of
the (3D printed) enclosure, with a grille at the other [1] ensuring
air was also forced under the driver modules (that sit above the RAMPS
board).

Cheers, T i m

[1] Part of an efficient cooling procedure can be fully managing
airflow through an enclosure. Having fans that just blow the same air
round and round isn't going to help. When I built my home server I
used a std PC mini tower case and blocked up all the vent holes except
those under the front panel and (of course) the PSU output. I also
added ducting inside the case ensuring the cold air drawn in though
the front went over the hard drives before being forced over the mobo
(RAM / CPU / Bridge) before being extracted through the PSU and out
the back. Therefore, natural convection would also help the process
and the result is the whole thing runs very cool. I've since replaced
the std ATX PSU for an external 'brick' and so the only thing in the
PSU case now is a single 120mm slow speed (=silent) fan. ;-)

[Brian Gaff]

Well, the thing is, what are their working temperatures supposed to be, and
are they exceeding this, if they are then if they are still working maybe
there is a power supply fault elsewhere, which will do for them in the end
by pusing up their dissipation. Not all chips can be used with a heat sink
unless internally the thermal conductivity is high enough to allow the heat
to be dissipated in one.
I assume these are surface mount chips, so the area available is going to
be very small.

Certainly you could try just standing some on the chips with some hs grease
in between but keeping them there is a whole other issue if there has been
no provision for sinks in the first place.
As for fanning do you really want the sound of a fan in your home cinema?
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"Mr Sandman" wrote in message
...
Hi peeps,
I have an Onkyo 5009 AV Reciever with the very common problem of overheating
HDMI board. You can see it just under the grill for cooling in the case. I
have an infrared heat sensitive camera and discovered there are several
small ic's that get very hot very quickly- i.e. 70-80c. The ICs are very
small, 10mmx10mm up to 10mmx16mm and thereabouts but there is space of about
an inch above so room for a heat sink maybe. I could Fit heat sinks to those
chips(if there are any small enough) or fit fans above or both. But does
anyone have any experience cooling small chips like these?

Cheers

Steve

[The Natural Philosopher[_2_]]

On 26/07/17 17:09, Brian Gaff wrote:
Well, the thing is, what are their working temperatures supposed to be, and
are they exceeding this, if they are then if they are still working maybe
there is a power supply fault elsewhere, which will do for them in the end
by pusing up their dissipation.

most silicon runs at up to 175 junction, and that can be easily 100C
case on small chips.


--
Gun Control: The law that ensures that only criminals have guns.

[Clive Arthur]

On 26/07/2017 17:58, The Natural Philosopher wrote:
On 26/07/17 17:09, Brian Gaff wrote:
Well, the thing is, what are their working temperatures supposed to
be, and
are they exceeding this, if they are then if they are still working maybe
there is a power supply fault elsewhere, which will do for them in the
end
by pusing up their dissipation.

most silicon runs at up to 175 junction, and that can be easily 100C
case on small chips.

'Most' is not true. Some does - even if it's rated at 85'C - but you
need to be aware of the limitations in both performance and longevity.

Cheers
--
Clive

[[email protected]]

On Wednesday, 26 July 2017 21:02:52 UTC+1, Clive Arthur wrote:
On 26/07/2017 17:58, The Natural Philosopher wrote:
On 26/07/17 17:09, Brian Gaff wrote:

Well, the thing is, what are their working temperatures supposed to
be, and
are they exceeding this, if they are then if they are still working maybe
there is a power supply fault elsewhere, which will do for them in the
end
by pusing up their dissipation.

most silicon runs at up to 175 junction, and that can be easily 100C
case on small chips.

'Most' is not true. Some does - even if it's rated at 85'C - but you
need to be aware of the limitations in both performance and longevity.

yes, running them that hot gives short life expectancy.


NT

[The Natural Philosopher[_2_]]

On 26/07/17 22:57, wrote:
On Wednesday, 26 July 2017 21:02:52 UTC+1, Clive Arthur wrote:
On 26/07/2017 17:58, The Natural Philosopher wrote:
On 26/07/17 17:09, Brian Gaff wrote:

Well, the thing is, what are their working temperatures supposed to
be, and
are they exceeding this, if they are then if they are still working maybe
there is a power supply fault elsewhere, which will do for them in the
end
by pusing up their dissipation.

most silicon runs at up to 175 junction, and that can be easily 100C
case on small chips.

'Most' is not true. Some does - even if it's rated at 85'C - but you
need to be aware of the limitations in both performance and longevity.

yes, running them that hot gives short life expectancy.

not really.


NT



--
€œBut what a weak barrier is truth when it stands in the way of an
hypothesis!€�

Mary Wollstonecraft

[Clive Arthur]

On 27/07/2017 01:31, The Natural Philosopher wrote:
On 26/07/17 22:57, wrote:
On Wednesday, 26 July 2017 21:02:52 UTC+1, Clive Arthur wrote:
On 26/07/2017 17:58, The Natural Philosopher wrote:
On 26/07/17 17:09, Brian Gaff wrote:

Well, the thing is, what are their working temperatures supposed to
be, and
are they exceeding this, if they are then if they are still working
maybe
there is a power supply fault elsewhere, which will do for them in the
end
by pusing up their dissipation.

most silicon runs at up to 175 junction, and that can be easily 100C
case on small chips.

'Most' is not true. Some does - even if it's rated at 85'C - but you
need to be aware of the limitations in both performance and longevity.

yes, running them that hot gives short life expectancy.

not really.

Yes, really. The rule of thumb is a halving of life expectancy for
every 10'C increase above some reference point given by the
manufacturer. Often 10,000 hours at 150'C is used as a starting
guestimate if you don't have a reference point. That corresponds to
1250 hours at 180'C which is realistic.

Basically, diffusion and migration seem to follow the Arrhenius equation.

Cheers
--
Clive

[The Natural Philosopher[_2_]]

On 27/07/17 09:09, Clive Arthur wrote:
On 27/07/2017 01:31, The Natural Philosopher wrote:
On 26/07/17 22:57, wrote:
On Wednesday, 26 July 2017 21:02:52 UTC+1, Clive Arthur wrote:
On 26/07/2017 17:58, The Natural Philosopher wrote:
On 26/07/17 17:09, Brian Gaff wrote:

Well, the thing is, what are their working temperatures supposed to
be, and
are they exceeding this, if they are then if they are still
working maybe
there is a power supply fault elsewhere, which will do for them in
the
end
by pusing up their dissipation.

most silicon runs at up to 175 junction, and that can be easily 100C
case on small chips.

'Most' is not true. Some does - even if it's rated at 85'C - but you
need to be aware of the limitations in both performance and longevity.

yes, running them that hot gives short life expectancy.

not really.

Yes, really. The rule of thumb is a halving of life expectancy for
every 10'C increase above some reference point given by the
manufacturer. Often 10,000 hours at 150'C is used as a starting
guestimate if you don't have a reference point. That corresponds to
1250 hours at 180'C which is realistic.

Basically, diffusion and migration seem to follow the Arrhenius equation.

Cheers

Yes, but there is a difference between 'short' and 'shorter'

10,000 hours at 150C is still a pretty long time at 80C

If we take a year at 150C that's 128 years at 80C

Experience suggests that unless you are running right on the limit, in
which case the chips tend to unsolder themselves, your product lifetmime
will be limited by other factors.

What tends to happen more is that chips go out of spec when hot.

However if the design calls for them to run at 80C then they will be in
spec for that anyway.


--
"The great thing about Glasgow is that if there's a nuclear attack it'll
look exactly the same afterwards."

Billy Connolly

[Clive Arthur]

On 27/07/2017 10:43, The Natural Philosopher wrote:
On 27/07/17 09:09, Clive Arthur wrote:
On 27/07/2017 01:31, The Natural Philosopher wrote:
On 26/07/17 22:57, wrote:
On Wednesday, 26 July 2017 21:02:52 UTC+1, Clive Arthur wrote:
On 26/07/2017 17:58, The Natural Philosopher wrote:
On 26/07/17 17:09, Brian Gaff wrote:

Well, the thing is, what are their working temperatures supposed to
be, and
are they exceeding this, if they are then if they are still
working maybe
there is a power supply fault elsewhere, which will do for them
in the
end
by pusing up their dissipation.

most silicon runs at up to 175 junction, and that can be easily 100C
case on small chips.

'Most' is not true. Some does - even if it's rated at 85'C - but you
need to be aware of the limitations in both performance and longevity.

yes, running them that hot gives short life expectancy.

not really.

Yes, really. The rule of thumb is a halving of life expectancy for
every 10'C increase above some reference point given by the
manufacturer. Often 10,000 hours at 150'C is used as a starting
guestimate if you don't have a reference point. That corresponds to
1250 hours at 180'C which is realistic.

Basically, diffusion and migration seem to follow the Arrhenius equation.

Cheers

Yes, but there is a difference between 'short' and 'shorter'

10,000 hours at 150C is still a pretty long time at 80C

If we take a year at 150C that's 128 years at 80C

The rule of thumb equation doesn't apply at lower temperatures, only
when diffusion gets going.

Experience suggests that unless you are running right on the limit, in
which case the chips tend to unsolder themselves, your product lifetmime
will be limited by other factors.

Lead free solder melts around 220'C, nobody uses ordinary tin/lead
(~183'C) at high temperatures. (Although in extreme situations, ~95% Pb
HMP solder is used which melts at around 300'C.)

What tends to happen more is that chips go out of spec when hot.

However if the design calls for them to run at 80C then they will be in
spec for that anyway.

I make a living designing electronics for use in 180'C ambient. It's
fun, because of the constraints - you can't just throw a big processor
at a problem, small geometries don't do well.

Cheers
--
Clive

[alan_m]

On 26/07/2017 10:30, Dave Liquorice wrote:


Fans really only work if there is a decent hot surface area to
transfer the heat, they are noisey and wear out. I'd find the largest
heatsinks that'll fit and sticke 'em on and then see what the
temperatures are.


I agree, the heat sink is the first thing to try

In some equipment I've fitted a 60mm fan to the underside of the top
casing blowing out through the existing ventilation slots and reduced
internal component temperatures by 20C. The fans have been set to only
run at a very reduced speed so noise isn't a problem [Pick a fan with a
low operating speed and then reduce the supply voltage]. I've fixed the
fan to the casing with cheap/thin/flexible cable ties around the solid
bit between the casing ventilation slots.

My Onkyo has a recommendation for at least 4 inches of free space above
the top of the casing which may not be achievable with many under TV
shelves/cabinets.

--
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