Another USB-C dock teardown

Disclaimer

Over the last year, I’ve been contacted by several USB-C accessory brands to test and review products. Some dodgy brands asked me to purchase via Amazon and then reimburse me after posting a review. I did not take them up on any such offers.

But a few brands seemed to actually want my feedback without any sort of Amazon scam. They sent devices at no cost to me and with the understanding that my review may be positive or negative and may involve teardowns to examine the internals. I intend to donate any provided products to charity (if they survive the teardown).

With that out of the way, lets get to it.

The Review

I was sent the 15-in-1 USB-C docking station by Choetech (also sold under the 4URPC, LASUNEY, EUASOO, and several other brands). Unboxing was uneventful – just a simple thin cardboard box with two smaller boxes inside. One contained the Dock which weighed ~330g and the other had a power brick (12V @ 3A) weighing 190g. Also included was a user manual, a card inviting me to a Facebook group, and 2 generic 1m USB-C cables with no logos or markings on them. While these cables are not e-marked, Choetech claims they will work at 100W when used with the Dock – and they are only intended to be used with the Dock.

The Dock itself looked and felt quite nice. with an unassuming size of ~115mm x ~60mm x 73mm. All the ports were aligned to the chassis well and cables were easy to plug and unplug. The two front USB ports were a little tricky to use since they were separated by only ~3.5mm. Plugging in a larger flash drive partially blocked the other port unless I carefully angled everything in together. While the Dock did have rubber feet on the bottom, the weight was not enough to keep it firmly in place while plugging in cables. The tension of video cables tended to slant the dock over to the side unless I had everything bundled up with zip-ties. A minor issue and comparable to other upright docks in this price class ($75-125 USD).

I plugged in the included power brick, my own 90W USB-C power adapter and a variety of devices. Dual 1080p monitors worked OK out of the HDMI ports. I did not try 4K (although the manual claims support for 2x 4K30 or 1x 4K60 and is backed up by the internal component capabilities). USB devices like mice, keyboards, fans, flash drives, and external hard drives all worked OK. I would have liked additional rear USB ports. I prefer to route all my cables to the rear and after running mouse and keyboard I didn’t have any left and was forced to use the front-facing ports cluttering up my desk. I did not measure transfer speeds as this is an uninteresting detail in this class of Dock since there are so many models using similar PCB layouts and components. Ethernet was functional as was the front-facing audio. The front USB-C port worked to charge my phone in USB-C PD mode at 10W and 15W (5V @ 3A). And the USB-C power delivery passthrough for charging the laptop worked OK at ~40-60W – I did not test >60W charging as I didn’t have a suitable laptop on hand during this time period.

I used the dock for 8 weeks and it performed well and didn’t get hot. The only issue I had was a few times my laptop did not come out of sleep while connected to the dock – but I suspect this is an issue with the laptop itself and not the Dock as I could not reproduce it consistently. Overall, it is a pretty typical budget Dock in a slick form factor.

There are two annoyances or quirks with this dock:

1. The Dock includes an extra USB-C host port and HDMI port (labeled HDMI1 and HOST1). The marketing materials show dual-PC workstations, but I can’t see how this would be helpful. There is no KVM functionality. The PC connected to HOST2 has both power delivery and dock functionality, while HOST1 has nothing except a single HDMI port. IMHO, the PCB real-estate would have been better used for more USB ports. And rather than integrate one, a discrete USB-C -> HDMI dongle would work just as well.
2. it needs 2 power supplies. The included 36W unit only powers the Dock electronics and downstream USB devices while a separate USB-C PD unit (not included) is needed to charge the laptop. This complicates setup and adds to cable clutter.

Both of these quirks are solved in a Dock from an alternate brand in the same style and form factor which I would recommend over the Choetech model. On sale for $68, the Choetech is still a fantastic deal. For the $110 list price (or ~$94 with discount codes) it is OK, but I think there are some better options depending on what ports you need.

Teardown

So I totally goofed on this teardown and ended up destroying the dock. I’m so embarrassed. The key issue I had was separating the nicely machined aluminum chassis from the plastic cage holding the PCBs. There were no exposed fasteners and I could not free it with heat or spudgers. So I used a cutoff wheel and sliced the aluminum apart. That was my first mistake. Even though I wore gloves, a mask, and wetted everything down, the aluminum powder went everywhere. Yuck. Then I dug in way too deep with the cutoff wheel and cut into the PCB and plastics because I didn’t mount the Dock in my vise properly. Then I ended up crushing part of it in my vise once the aluminum gave way. I tried hammering the aluminum back into shape, but no go. She’s a goner.

The power brick survived unscathed:

Inside the dock were two metal weights totaling 76 grams. These along with two rubber feet on the dock didn’t do much to help it stay in place on a smooth desk surface but did give the dock a more solid feel overall.

The main PCB appears to be 3 layers. Key components on the front:

• Via Technologies VL817-Q7 4-port USB 3.1 hub
• Soldier Electronics “SLT2411” (SOP-24) – inductor array for power filtering
• Puya semiconductor P25D40H flashRAM
• 2 SOP-8 chips labelled with “KS 3310 D3LL6” – probably power management ICs or dual P-channel mosfets
• 220uF 16V bulk power input filter cap
• 2x 220uF 10V output filter caps for the USB ports
• 3.5mm x 1.0mm power barrel jack
• 3x USB-C ports
• 1x Ethernet port
• 1x VGA port
• 3x HDMI ports
• Note the unpopulated SOP-8 solder landings near the Ethernet port

On the rear:

• Via Technologies VL103R-Q4 DP alt-mode & PD 3.0 controller
• Realtek RTD2183 DisplayPort 1.4 MST hub with 1x HDMI , 1 VGA, and 2x DP++ drivers built-in
• Texas Instruments SN75DP149 DP->HDMI re-timer (
• Techcode TD1583 (SOP-8) PMIC
• Realtek RTL8153 Ethernet
• A QFN-28 IC marked with “L170 3840 031” – probably a microcontroller
• status LED surrounded by black foam shield
• The Ethernet Jack is on its own tiny PCB which is soldered to the main PCB with 18 ~2mm standoffs – 7 of which are connected to ground. This is one way to get the USB and Ethernet ports aligned on the same plane – a nice touch. Other docks will just have the USB ports recessed by ~2mm with respect to the Ethernet port.

Components dedicated to the separate USB-C->HDMI converter:

• A second Via Technologies VL103R-Q4 DP alt-mode & PD 3.0 controller
• A second QFN-28 IC marked with “L170 3840 031” – probably a microcontroller
• Parade PS176HDM USB-C -> HDMI 2.0 controller
• A second Puya semiconductor P25D40H flashRAM

The larger PCB connects to a smaller one with a ribbon cable. While the ribbon cable is held in place with latching headers, a generous amount of white putty was applied to prevent it from shaking loose. This bottom houses a USB-C connector, USB-A, and a 3.5mm TRRS audio jack:

Remember how I said I ruined the PCB? Well I managed to dislodge the audio chip. Ooops. Well here are the notable components:

• Another Via Technologies VL817-Q7 4-port USB 3.1 hub is a QFN-76 package
• Realtek ALC4042 Audio chip. QFN-32
• Another Puya semiconductor P25D40H flashRAM (Why more flashRam? This second board is probably meant to be used standalone or paired with a variety of other boards.)
• SOP-6 power management IC (markings unclear)
• 3x 220uF 10V power output filtering caps for the USB ports
• additional USB port

Here is the rough component topology of the main Dock:

• USB-C Host port
  • Via VL103R-Q4 DP alt-mode & PD 3.0 controller
    • Puya semiconductor P25D40H flashRAM
    • 2 SOP-8 chips labelled with “KS 3310 D3LL6” – probably power management ICs or dual P-channel mosfets
      • USB-C PD port
    • A QFN-28 IC marked with “l170 3840 031” – probably a microcontroller
    • Realtek RTD2183 DisplayPort 1.4 MST hub
      • HDMI 1.4 port
      • Texas Instruments SN75DP149 DP->HDMI re-timer
        • HDMI 1.4 port
    • Techcode TD1583 (SOP-8) PMIC
    • Via Technologies VL817-Q7 4-port USB 3.1 hub
      • USB 3.x port
      • USB 3.x port
      • Realtek RTL8153 Ethernet
        • Ethernet Port
      • Ribbon cable
        • Smaller PCB:
          • Via Technologies VL817-Q7 4-port USB 3.1
            • USB 3.x port
            • USB 3.x port
            • Puya semiconductor P25D40H flashRAM
            • USB-C port 5Gb/s / 15W
            • Realtek ALC4042 Audio chip. QFN-32
              • 3.5mm TRRS

Separate USB-C->HDMI 2.0 converter topology:

• USB-C Host port
  • Viatech VL103R-Q4 DP alt-mode & PD 3.0 controller
    • A QFN-28 IC marked with “l170 3840 031” – probably a microcontroller
    • Parade PS176HDM USB-C -> HDMI 2.0 controller
      • HDMI 1.4 port
    • Puya semiconductor P25D40H flashRAM

Additional reading