Xperia Z5 Thermal dissipation

Although it was known in the Android community from other high-end smartphones already released this 2015 year that the Qualcomm Snapdragon 810 suffered of overheating in their first die revision (you can take a look to my previous article) it seems that Sony decided go ahead with it in their latest high-end Xperia Z5 family.

Although not mentioned, it is most than probably that Sony is using the die revision 2.x of it, which suffers lower over heating but anyhow noticeable by the user if you use the SoC at maximum throttle (as gaming).

However, it looks like Sony decided to introduce some extra thermal dissipation techniques coming from higher size consumer electronics equipment or computers; more complex but also efficient to spread the heat along the phone, instead of a single heat sink point above the SoC.

In next pictures you can see how Sony added a couple of thermal copper heap pipes connected to a bigger heat sink and even thermal paste on top of the SoC, which makes more complex (and expensive) the inners and assembly of the Z5 phones family, but less noticeable to the user when the SoC warms up:


And for the Z5 Premium:


Of course, these kind of techniques are not very usual in high integrated smartphones due the higher manufacturing costs, labor time and lower reliability at long term. I assume that Sony Mobile R&D team had to make some trade-off’s this year to be able to release a newer Z family member with higher specs (currently 810 v2.1 is the highest, while the 820 is ready to be released) able to compete with the strong competition coming from China (as the OnePlus, Huawei, Meizu, Mi, Lenovo/Motorola), Korea (Samsung/LG) and for sure, Apple with their iPhones.

Moto 360 – Skeuomorphism cannot be always the best

There are many discussions about which is the best shape for a smartwatch: Round or Square; and even in the Android world you can find examples for both:

  • Pebble Time: Square (Rectangular)
  • LG G Watch: Square
  • LG Watch Urbane: Round
  • Samsung Galaxy Gear Live: Square (Rectangular)
  • Sony Smartwatch: Square
  • Motorola Moto 360: Round

Apple decided to choose for the Square flavor for all its models of the new product line.

Well, we could debate plenty about who is right or wrong, but here I want to take a look to the insides of the Moto 360 and the trade off in its internal design to make it round.


The first thing that we see inside of it, its is Heart Rate sensor, much smaller than Apple approach, but based in the same methodology known as photoplethysmography.


For your information, it’s theoretically capable of also acting as a pulse oximeter for assessing your oxygen saturation level. However, as far as we know, these enhanced capabilities are not (yet) enabled, neither for the Moto 360 or Apple Watch due lack of 100% accuracy always under all kind of circumstances.

Then, once opened, the first thing that you see is the screen flex cable connected to the main board, which also has an RF shielding on top all the circuitry:


And further, at the other side, its 300mA battery, which is not round at all, unless you doubt about it 😉 ; so limiting its maximum capacity size to the diameter of the round watch:


In the other side of the bottom plastic cover, we can see the inductor for the wireless charging power system, which follows the Qi inductive power transfer standard, (which is most “de facto” nowadays standard):


And then, finally, we reach the PCBA (Top and Bottom views) with all the tiny components reaching all the limits of the round shape at top side:


It is pretty cool (from the electronics point of view 😉 , as Apple Watch made a higher system integration, but also more expensive) to see how the PCB designer used up to the last piece of area.

Moreover, we can identify some of the main IC components on it:

  • TI – TMS320C5545: DSP (for Voice processing)
  • TI – WL18G/31/46C1VRI: Wireless transceiver module, handling Wi-Fi (but not enabled), Bluetooth, and Bluetooth Low Energy protocols
  • Micron – MT46H128M32L2KQ-5 IT: 500MB LPDDR SDRAM
  • Toshiba – THGBMAG5A1JBAIT: 4GB NAND flash (e-MMC interface)
  • Solomon Systech – SSD2848K1: Display controller (driving the LCD)
  • Atmel – MXT112S: Capacitive touchscreen controller
  • TI – AFE4490: AFE for the pulse oximeter sensor
  • TI – 1211A1: USB 2.0 PHY transceiver (for inner user or debug)
  • TI – TPS659120: Power Management Unit
  • TI – BQ51051B: Wireless Power Li-Ion Charger Receiver
  • Wolfson Microelectronics (Cirrus Logic’s) – WM7132: MEMS microphone
  • Wolfson Microelectronics (Cirrus Logic’s) – WM7121: Second MEMS microphone (companion for noise cancelation)
  • InvenSense – MPU-6050: Single package MEMS Six-axis accelerometer + Gyroscope

And then one of the cool things is the CPU, which is located just underneath the Micron SDRAM package, which is a TI – OMAP3630, labeled as X3630ACBP:


It is a SoC from some years ago, but with the Software optimized, powerful enough to have the smartwatch’s responsiveness consistently snappy and cheaper.

For instance, Apple developed its own SoC, but for Motorola/Lenovo, this integration approach was cheaper than developing a SoC from scratch, or paying IP royalties to newer CPU vendors.

Besides, for those who remembers that in old days Motorola made their own chips, remember that Motorola spun-off its semiconductor unit (Freescale today, and next year part of NXP); so as you see, they mostly invested in TI chips rather than other suppliers.

Finally, you can see how looks like the circular LCD screen of  it:


Although circular screens are not mainstream, we assume this LCD solution approach was cheaper than an OLED option, even taking into account the lighting and power consumption drawbacks of this screen technology compared with OLED.

Well, my last comment will be regarding its ‘ugly’ LCD’s bottom side ‘black line’ characteristic, which you can clearly see in this photo:


There is located the ambient light sensor. And although I don’t know if Motorola (Lenovo) deeply studied another possible location for it; unfortunately, it really destroys all the ‘hype cool‘ thing of having a non-pure UX rounded screen smart watch 😦

HOW TO Improve your WiFi coverage simply reorienting your router

Nowadays, all of us relies on wireless connectivity everywhere we go: at home, at office, at school, and also at shops and streets while we are walking.


It is true that for wireless cellular coverage there is not so much that we can do to avoid what are called as “Dark Spots“, as we cannot change the topology of the mobile cellular data network, only move ourselves in the street to find out the best place with higher cellular reception looking the coverage bars changing in our smartphone.

But our home, the situation is different. Most of the times we lose 2.4GHz/5GHz wireless coverage or simply we don’t get the maximum throughput from our WiFi routers simple because they are not in the ideal location by few inches, or even by wrong orientation (remember that most of the regular current market wireless routers have embedded antennas instead of external whip antennas, so you cannot change the antenna orientation neither their angle if you don’t simply re-orient the whole router, which in fact is what we are proposing your here).

Well, in the following video you will be able to see a simulation of the WiFi RF signals propagating inside an apartment example, and how moving slightly the router which transmit them, you can reach further rooms or far corners of it:

It shows you as slightly moving few inches your wireless router (represented as the Bottom-Right GREEN DOT) from its position/orientation, you can reach even the further rooms and Dark corners WiFi coverage areas in your apartment.

Of course, each one of us has a different appartment floorplan, and thanks to WiFi Solver FDTD, an Android app developed by Jason Cole, you can also upload your own floorplan on it and simulate the coverage at home.

Qualcomm Snapdragon 810 could suffer overheat [Updated x1]

Some months ago there were some rumors saying that the upcoming Qualcomm Snapdragon 810 thought for this 2015 year high-end smartphones had some overheating issues.


This was also one of the reasons why those rumors suggested the decision of Samsung to disregard this processor and use only their own Exynos in their Galaxy S6 and S6 Edge new 2015 series.

Well, today (Dutch specialized site) was evaluating the HTC One M9 (which uses this 810 CPU), and discovered that when high-performance games as Asphalt 8 and Assassin’s Creed are running, the temperature of the M9 case gets much warm that the HTC competitors, in fact, up to 55,4°C.

You can see it in their thermal picture that they made:


It is true that the test was not done with the final SW Android OS build for the HTC One M9, but anyhow it doesn’t show very good perspective. There will be more high-smartphones using this high-end CPU on 2015, so if it is a real issue, we will see more reports like this one and users complaining in the coming months.

[Update x1: 26 March 2015]

After the shocking results shared by couple weeks ago, HTC released a new Android OS build (claimed to be more stable and closer to the final release) where the temperature of the HTC One M9 is reduced by -13,7°C down to 41,7°C, something closer to its competitors:


The official details of what was exactly changed has not been officially disclosed by HTC, but pretty sure HTC reduced the processor performance (freq. clocks in some domains) in extreme cases as high demanding 3D games.

Now, we will have to wait for newer HTC One M9 benchmarkings using the tweaked new Android OS build, which still is not the final one, to see if it still can compete face-to-face against latest Samsung Exynos 7 or Apple A8.