Garmin Fenix 5X inner parts, teardown, disassembly, assembly etc… (No Disassemble! )

____________________________________________________________________

When I see some circuit boards, get my camera out and take some photos. This time my turn was for 5X. Fenix 5X is ’s sport watch from Fenix series. What makes it different from other Fenix 5 watches is MAPS and mapping functions. It can display the map of the area, search in the map and help you navigate around using the map. It was released last year and released other products based on that platform. Now lets dive into the watch.

Garmin Fenix 5X

Garmin Fenix 5X

Garmin Fenix 5X watch body is sandwiched between two metal parts. Upper part is the display bezel and lower part is a large metal around optical HR sensor. To go inside you need to remove the 5 screws on the bezel. Yeah, this is an old school application customer friendly companies used in the past. Nowadays, especially stupid phone companies use glues, glasses and metals to build products. So if you need to repair anything, you either destroy your smart device or have to pay the price of a new one to service it. Display is glued to the bezel and display connector is connected to the motherboard.

Back of the bezel with the gasket

Back of the bezel with the gasket

Bezel is completely painted black or gray, both outside and inside. Water protection is done via a black gasket. If you need to open your watch be careful with the gasket, or you can loose its water resistance and have a bricked watch…

Display is glued to back of the bezel. It’s smaller compared to Fenix 3 display backside. On this module backlight is better distributed around the screen. Fenix 3 display had a single led and at that point the display was brighter. I haven’t checked for any such LED with Fenix 5X display. Also I couldn’t find a detailed information about producer of the display. It may still be JDI as the producer of Fenix 3 display, but I couldn’t find any detailed info in its wearable product pages.

Watch housing houses a big motherboard with a GPS antenna on top of it. GPS antenna is easily removable. Motherboard is held by some screws. Below the motherboard there are optical HR sensor unit, vibration engine and barometer module and USB connection and charge connector pins. Heart rate sensor seems molded into the backcase and I didn’t try to removing the screws from the back plate.

5x housing

5x housing

Vibration unit is different than Fenix 3 vibrator which was a rotation based motor. Fenix 5 vibrator is more like the taptic engine of the iPhone’s. First I thought it was a large capacitor or a second battery to hold the time. Then I found out it needed a vibrator so that it can vibrate when needed. 😀 Barometer sensor is also mounted via screws like Fenix 3 HR. Fenix 3 sensor was glued or molded someway. It measures the air pressure and pressure changes with temperature and these data is used to calculate the elevation accurately. Or as accurate as possible as it doesn’t work as intended everytime, due to change in pressure and some bad software fine tuned settings. I think this chip needs some hot showers from time to time. Two times a year it recorded mad altimeter readings and returned back itself. However, for some people id didn’t returned to normal levels and they replaced their watches from Garmin. You’ll need to remove the vibrator first if you need to replace the barometer sensor.

Fenix 5X battery and back of the motherboard

Fenix 5X battery and back of the motherboard

Below the mother board there is the battery. It’s a 430 mAh, 1,63 Wh 3.8 v battery. Larger capacity than Fenix 3 battery but survives less with me… It’s made by Routejade Inc. and model number is ASDB542437-P1. UPS, I googled it and found no Ebay etc. results. We have to have the Garmin replace the batteries or contact Routejade in South Korea if they’ll ever sent a single battery.

In the front side of the motherboard, almost everything is under an EMF shield. There is a buzzer attached to shield.

Mainboard front

Mainboard front

Under the shield we see all the beautiful internals of the beast.

Fenix 5X motherboard with chips...

Fenix 5X motherboard with chips…

Lets list some of the chips.

16GB THGBMHG7C1LBAIL 16 GB e-MMC NAND Flash module made by Toshiba. This is the chip where those GB sized maps and our activities, apps etc. lies.

Toshiba 16GB THGBMHG7C1LBAIL

Toshiba 16GB THGBMHG7C1LBAIL

Winbond W948D6FBHX5E 256 Mb (256 Mb / 8 bits = 32 MB) Low Power Double Data Rate Synchronous Dynamic Random Access Memory. In short it’s the RAM chip where map data is stored during activities so that processor can access the data fast. When we go to map screen of the activity, map data is loaded from the flash memory to this RAM chip and processed from there. Also CIQ applications can access about 1 MB of it. I think Garmin Epix RAM chip was 32 MB too.

Winbond W948D6FBHX5E

Winbond W948D6FBHX5E

Freescale (now NXP) Kinetis SCK61FN1M GUCK12 This is probably the brain of the watch. ARM Cortex M4 processor made by Freescale (Now NXP). 12 number behind the GUCK12 code means it can run at 120 MHz frequency. It has 1 MB of flash memory and 128 KB RAM on it. But anyway it can access 16 GB of NAND storage and 32 MB of RAM. 😀 I think this was the chip we saw in the FCC PDF files of Garmin Epix. Then why they used the old chip in a newer watch? Probably Garmin devs. wanted to use the same platform that they know it works. They may have codes specific to processor and don’t want to write it again for another. This may be the appropriate chip they need to use with external NAND memory and RAM. Also even 180 MHz Fenix 3 processor is faster than this, why? Wearable devices have battery concerns, so chips aren’t run at full power. Instead they are run at lower frequencies so that they save power and doesn’t get hot like mobile phone processors. So both watch processors are probably running at much lower frequencies. Also both Garmin Epix and Garmin Fenix 5X scores higher than Fenix 3 in ConnectIQ benchmark apps. This means Garmin lets this slower processor run faster than Fenix 3 processor. Then why Garmin doesn’t use the same processors in all watches? They have different needs. Fenix 5X needs external DDR memory for maps and GBs of storage but Fenix 3 doesn’t. So they may have preferred a chip with DDR controller in Fenix 5X and a chip with 256 KB internal RAM in Fenix 3 or maybe even Fenix 5.

Freescale Kinetis SCK61FN1M GUCK12

Freescale Kinetis SCK61FN1M GUCK12

MAX 32620B Maxim Integrated 96 MHz ARM Cortex-M4 processor with 2 MB internal flash and 256 KB internal SRAM. This is another chip probably playing some of the brain role in the watch. It can run at 4 MHz for always on sensors monitoring. It maybe running the watchfaces, widgets etc. and acting as sensor hub and the Kinetis processor may be running the GPS activities etc.

MAX 32620B

MAX 32620B

MAX 20303 Maxim Integrated power and battery management chip.

Maxim MAX 20303

Maxim MAX 20303

N52832 Nordic Semiconductor nRF52832 BLE/ANT chip. This chip is responsible for the Bluetooth Low Energy connection between your watch and phone. Also ANT+ and BLE sensors are connected via this chip. It’s 32-bit ARM® Cortex™-M4F CPU with 512kB flash and 64kB RAM and can run at 64 MHz clock speed.

Nordic Semiconductor N52832

Nordic Semiconductor N52832

ATWILC 1000B UU Atmel WiFi 802.11 b/g/n WiFi Module with 72 Mbps max. data rate.

Atmel ATWILC 1000B UU

Atmel ATWILC 1000B UU

ST TULI1B ST Microelectronics STULPI01 high-speed USB 2.0 transceiver. Seems this chip is responsible for the USB connection to a computer. This does the job while I transfer my weekly OpenStreetMap updates to the watch.

ST TULI1B

ST TULI1B

MTK ARM 3333AV Under the EMF shield, in a rather outer compartment lies the GPS chip responsible for listening and tracking GPS + Glonass signals and return location data to processor, so that we can see where we’re on the map and know how fast we’re running and riding or swimming etc. It has a 158 MHz ARM7EJ-S CPU with some internal memory and supports GPS, Glonass, Beidou, Galileo etc. but we can only use it for GPS + Glonass with Fenix 5X. It’s the same GPS chip in Fenix 3. But sometimes I think this one has a higher madness level, looking at the GPS tracks of the watch. 😀

MTK 3333AV GPS chip with antenna connectors

MTK 3333AV GPS chip with antenna connectors

There are many other chips probably working as accelerometer, gyroscope, compass etc. But they’re too small to see and to capture. So I can’t see which company produced those sensors.

Apart from chips there is another part inside the watch close to GPS module and above the connection pins of it, the GPS antenna. Three gold pins on the motherboard connects it to the GPS module. Now it is different than the one in Fenix 3. Apparently Garmin read the hundreds page GPS accuracy posts in its Fenix 3 forums and tried to do something. Now, Garmin placed GPS chip in a rather outer place under the metal shield. Then they changed the antenna structure. Result is better or worse, depends on the situation and the user. Fellrnr tests say it has worse accuracy than even Fenix 3. For me, previously I had some bad and strange jumps out of the route but it’s OK for me. My main problem with the GPS now is, false max. speed values. It’s either above a human can do or it’s below the average speed. And there seems no update about this and I tested it with two F5X’s…

Garmin Fenix 5X GPS Antenna

Garmin Fenix 5X GPS Antenna

In a corner of the watch there is another antenna. That’s not some external antenna, just build on the PCB. That’s the antenna used for BLE, ANT+ and WiFi.

Fenix 5X BLE ANT+ WiFi Antenna

Fenix 5X BLE ANT+ WiFi Antenna

For me Garmin Fenix 5X is a good watch to wear. It does its stated job and doesn’t have high specs found in smart watches, resulting in actually freely usable watch without the fear of battery. I don’t have to charge it every night, I reserved that duty for only my smart phone. And sometimes my bike lights. It has the features I need, with some mapping features I was missing with Fenix 3. It has its flaws. GPS is not perfect with walking and running. But almost perfect with biking, except it sometimes records excessively high max. speeds after pausing and resuming an activity. However, when I look at the whole package it definitely fits my needs. However, industry is changing and its getting new rivals. I’m not sure I’ll follow the next Garmin Fenix with those prices. Xiaomi Amazfit Stratos for example, similar features with much cheaper price. If it gets Ant or BLE sensor support with some mapping ability in the future models, anybody can go after it. Actually, Garmin should do a lot to be different than such cheaper alternatives but they even can’t release a stable software in two or three months. Or even can’t release betas with solutions for issues of previous betas…