Thermal performance of Peter's P2D2 in 3 different orientations

Some quick thermal pics of P2D2 with silicon loaded (glob top):-

1. Normal orientation with glob top of chip pointing upwards - see FLIR0496 - 72 degrees C

2. Upside down orientation with big ground plane pointing upwards - see FLIR0497 - 58 degrees C. The silver pad on the reverse side of the board doesn't play by the usual emissivity rules, hence the dark square, but this will actually be the hottest area.

3. (no cap) but side-on orientation had a peak temp around 70 C.

These test using the torture test suite running 8 cogs at 180 MHz. P2D2 was taking 280mA at 5V overall. The XCL220 reg hardly raising a sweat

Camera is a Flir C3. Its not designed for closeup circuit boards like the more expensive $3k flirs, but actually works fine. However the IR and visual cameras are about 20mm apart, and this causes an offset between the visual (edges) and IR (colours) in the combined image that it outputs, when you use it for close up work.

320 x 240 - 67K
320 x 240 - 80K

Comments

  • 24 Comments sorted by Date Added Votes
  • TubularTubular Posts: 3,118
    edited October 5 Vote Up0Vote Down
    Actually we really need to stick a small bit of tape over the middle of the silver rear of p2d2 so we get the true peak which should be more than 58 C. The difference will prob end up less than 14 deg C
  • Awesome, Lachlan!!!

    I was running at 340MHz last night with increased VDD. Seemed to be working.

    Is this the spinning Fozzy torture test?
  • Brian, what on earth were we thinking this arvo testing glitches when we should have been testing turbo fozzie?
    That was ntsc though, wasn't it? But only greyscale, wonder if the modulator IQ issue kills greyscale too?

    340 MHz is amazing, Chip. And such a good low range on the PLL too. Certainly going to want a p2d2 overclockers edition, with 2 oz copper and programmable voltages like they do with PC CPU overclocking
  • T ChapT Chap Posts: 3,846
    edited October 5 Vote Up0Vote Down
    You can hold the button and move the laser point around and see changes real time. This might help to some extent for heat spread on the surface if you don’t have a Flir.
  • Someone recently asked for some whiz-bang demos, a TURBO Fozzie spinning at 340MHz would certainly qualify !!!
    Anyone up to posting some videos!?!

    A comparison of P1, P2 @ 180MHz and P2 @ 340MHz would be stelar!!
    Maybe it will be a new benchmark: Fozzie_spins/second :-)

    @Tubular
    YES !! Overclocking please :-)
    340MHz opens up some exciting new opportunities for P2 !

    j
  • Holy buckets! I thought 340Mhz was PLL number.

    You guys are clocking the silicon that high?

    Do not taunt Happy Fun Ball! @opengeekorg ---> Be Excellent To One Another SKYPE = acuity_doug
    Parallax colors simplified: http://forums.parallax.com/showthread.php?123709-Commented-Graphics_Demo.spin<br>
  • potatohead wrote: »
    Holy buckets! I thought 340Mhz was PLL number.

    You guys are clocking the silicon that high?

    I had raised VDD to 2.0V. When we get the real packages, they will be able to convey heat away from the chip better.
  • You would not want to design a product that runs the P2 at 340MHz, as it would require over-voltage and maybe active cooling. It would wear the chip down fast.
  • Of course not. But... some of us, when there are real chips, may have some fun.

    Do not taunt Happy Fun Ball! @opengeekorg ---> Be Excellent To One Another SKYPE = acuity_doug
    Parallax colors simplified: http://forums.parallax.com/showthread.php?123709-Commented-Graphics_Demo.spin<br>
  • Someone totally needs to do an overclockers edition. The 'product' is learning about overclocking. Call it the P2 Sparkler, burn it bright but brief.

    There was a P1 job I did once using Phil's 'propstick', the main program had a long list of things to do a bit like a 'PLC scan'.

    On that job, going from 6 MHz crystal to 6.25 MHz crystal kept the whole program in spin. Sure I could have gone to P1 PASM to gain speed, but its nice to have the option. With P2, we have many more PLL options to achieve the same
  • Tubular, how are you still up? You were going to bed four hours ago.
  • TubularTubular Posts: 3,118
    edited October 5 Vote Up0Vote Down
    Lets just say I have this cat...

    Actually I have a cat and 3 tame magpies that come to visit each morning for breakfast. They sing for it.

    The birds aren't as patient as the cat, and the cat comes to tell me the birds have arrived, and asks "are you going to feed me or should i help myself to the magpies?". Then i get up, feed the cat dog food (so he eats slower), and feed the magpies dry cat food (which they like), and then we all get on with our day.

    It's helped get me to work early during a busy few months, but unfortunately since work has slackened off a bit, the whole circus is tied to sunrise, and I'm looking forward to daylight saving starting this coming weekend, where all the above will happen at a respectable 6.30 rather than 5.30
  • I'm trying to wake fozzie now….
    Melbourne, Australia
  • ozpropdev wrote: »
    I'm trying to wake fozzie now….

    If there is no color modulation, it should work fine.
  • jmgjmg Posts: 12,064
    edited October 6 Vote Up0Vote Down
    potatohead wrote: »
    Holy buckets! I thought 340Mhz was PLL number.
    You guys are clocking the silicon that high?
    cgracey wrote: »
    I had raised VDD to 2.0V. When we get the real packages, they will be able to convey heat away from the chip better.

    I can see you asking OnSemi for a package with a top-thermal-pad too !! ;)
    cgracey wrote: »
    You would not want to design a product that runs the P2 at 340MHz, as it would require over-voltage and maybe active cooling. It would wear the chip down fast.
    There are quite a few overclocking and cooling offerings for the RaspPi & NanoPi
    They range from finned heatsinks, to full fan assemblies.

    This NanoPi Fan assembly example looks cute "Cooling Set + 3D housing, Irresistible Charm"
    https://www.fabtolab.com/nano-pi-m3-cooling-set
    or this
    https://andahammer.com/index.php?route=product/product&product_id=242
    http://www.nanopi.org/DUO-Heat.html

    That last one is remarkably close to a nice fit on the P2D2 - just needs a squeeze to fit the 4 mounting holes.
    Their heatsink uses 21.4 x 41.6 x 16 mounting holes on overall PCB 50 x 25.

    I found more images here, this looks like another variant heatsink, thicker ?
    https://forum.armbian.com/topic/7280-need-some-info-on-nanopi-duo/
    They appear to use a thermal pad, which squashes to give some tolerance.

    This is 2-D DXF PCB drawing, for the mounting holes (but sadly not the heatsink outline)
    For more details refer to the document NanoPi_Duo_v1.0_1706 pcb file in dxf format

    There is also a larger NanoPi NEO/NEO/NEO Plus2 Aluminum Heat Sink with Thermal paste and Screw pitch 35.4*35.4mm
    more choices :
    https://www.friendlyarm.com/index.php?route=product/search&search=heat+sink&description=true&sub_category=true


    Anyone happen to have a Nanopi-duo they can measure the height of the package/heatsink clearance ?

    If the clamping height is not P2 compatible, there are flat plane heatsinks too.
  • Ooh!!!
    Seems I may need to scavenge a heat sink/fan combo from a PC motherboard (CPU) to use on an overclocked P2.
    @lachlan, those 1500 chips might be in short supply as we burn thru them ;)
    My Prop boards: P8XBlade2, RamBlade, CpuBlade, TriBlade
    Prop OS (also see Sphinx, PropDos, PropCmd, Spinix)
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  • I'm thinking high-powered Peltier cooler.
  • jmgjmg Posts: 12,064
    cgracey wrote: »
    I'm thinking high-powered Peltier cooler.

    Why stop there, the real over-clockers use cryogenic cooling !! ;)

    The peltiers are a little niche, whilst you can get all sorts of plumbing + Fins + Fans for cooling PC'c to below 1'C/W levels, from many sources.
    There are videos of people out there, extreme cooling RaspPi etc, who are just a little nuts...
  • jmgjmg Posts: 12,064
    edited October 5 Vote Up0Vote Down
    cgracey wrote: »
    I was running at 340MHz last night with increased VDD. Seemed to be working.

    Another P2 avenue is under-clocking.

    To power match an All-COGs-Full P1, the P2 needs to run circa 44MHz, which happens to also appx match ns/opcode
    As voltage scales, the power scales faster & it seems 40MHz could run at greatly reduced Vcore ?

    eg at 40MHz, the power curves predicted look like this :
    Vcc=1.8 Pd = Cpd * Vcc^2 * Fi = 0.28512W
    Vcc=1.2 Pd = Cpd * Vcc^2 * Fi Pd = 0.12672W
    Vcc = 1.1 Pd = Cpd * Vcc^2 * Fi Pd = 0.10648W

    ie Be interesting to see the the MHz/Vcc envelope, and how low can Core supply go, to still operate digitally/analog ?

  • Delid one of the chips with a Bridgeport, then put some thermal compound on it and a metal heat spreader!
  • pedward wrote: »
    Delid one of the chips with a Bridgeport, then put some thermal compound on it and a metal heat spreader!

    The bottom of the chip is one big exposed thermal pad, just for that purpose. This package has a Tja of 20C/W.
  • YanomaniYanomani Posts: 635
    edited October 6 Vote Up0Vote Down
    cgracey wrote: »
    I'm thinking high-powered Peltier cooler.

    Are you thinking about something like this?

    thermonamic.com/TEC2-31-17-04-English.pdf

    - The size of its cold side seems to be a good fit for the exposed metallic surface, at the bottom side of P2D2 or any other pcb;
    - Its staggered construction would ease the placement of any smd components at the bottom layer, even at the near vicinity of P2;
    - Due to its multistage construction, it's intended to be applied were great temperature differentials are expected to occur;
    - Its overall thickness would keep any needed metallic heatsink away from pcb bottom layer, avoiding unnintended contact.
    - Use preferably spring-loaded fixtures to secure the heatsink to the board, as to avoid any bending associated to thermal expansion differences between them.

    Henrique
  • jmgjmg Posts: 12,064
    Another Peltier example of a full kit is here

    https://www.electrodragon.com/product/tec1-12706-thermoelectric-peltier-cooler-12v-60w/

    and you can see the down side issues - this adds a lot of extra watts, (many more than P2) which need serious total cooling.
    This comment too :
    These devices must be used together with a heat sink to avoid burned in 2 seconds after powered up


    Of course, if your target is to go below ambient, and not just close to ambient, then some form of active cooling will be needed.

    If doing all this, some temperature sense would be needed, and a DAC for VCore control too ...
  • Someone is going to drop one in liquid something.

    Maybe start with dry ice?

    OC fun and games ahead. It's all fun, until someone torches a chip. Best wait for the production run.

    Do not taunt Happy Fun Ball! @opengeekorg ---> Be Excellent To One Another SKYPE = acuity_doug
    Parallax colors simplified: http://forums.parallax.com/showthread.php?123709-Commented-Graphics_Demo.spin<br>
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