USB Hub + DAC
A USB C 2.0 hub with a built in audio DAC.
Created by
Person20020 (Koji) 🚀
Tier 3
19 views
1 follower
CAN ⚡🚀
approved USB Hub + DAC ago
Tier approved: 3
Grant approved: $59.00
nice project
Person20020 (Koji) 🚀
submitted USB Hub + DAC for review ago
Person20020 (Koji) 🚀
added to the journal ago
Fixed case and added BOM
I fixed the case by adding a wider area around the USB ports + 3.5mm jack so that cables overmold would be able to fit. I also added everything to the BOM.
chengyin.yao 🚀
requested changes for USB Hub + DAC ago
Nice project, but you probably forgot to order either the PCBA or the components from LCSC. You should also include the checkout page as the current page doesn't include shipping or taxes. Please also expand your readme a bit, and add a bom.csv
Person20020 (Koji) 🚀
submitted USB Hub + DAC for review ago
Person20020 (Koji) 🚀
added to the journal ago
Designed case
I exported the PCB and now have finished the case. Right now it is pretty simple so I might go back and add more to it before I print it. I added a bending button to the top for the mute button. This keeps it much thinner than the last attempt I made which used a large 12mm push button.
Person20020 (Koji) 🚀
added to the journal ago
Routed PCB Pt 2
I finished routing the PCB and had to make a few changes. First changing mono input to stereo for the mic seemed somewhat complicated so I decided to get rid of mic in. I also fixed the capacitors by moving to larger aluminum ones.
I added some mounting holes to mount to the case. I think I'll use some printed standoffs with m2 heat set inserts to mount it so I chose spots that have space around them to place the screw holes.
It seems like I somehow managed to get it to be 5mm smaller in each direction than the last attempt that I made at this.
Person20020 (Koji) 🚀
added to the journal ago
Routed PCB Pt 1
I routed the USB hub part. I haven't worked on the dac section yet but I have just now realized that some of the capacitors are supposed to be polarized and need to be larger electrolytic caps.
I did use some vias on my usb lines but it is only usb 2.0 so it should be fine.. (I think it can handle like 10cm or something)
Person20020 (Koji) 🚀
added to the journal ago
Finished Schematic
I finished drawing out the schematic. On the PCM2902 I decided to only connect the mute button as I prefer to control volume through my keyboard. The mute button probably won't be used very often but it shouldn't get in the way either.
Person20020 (Koji) 🚀
added to the journal ago
Made Schematic Part 1
I had previously started to build a USB hub but I never finished and I decided to just start from scratch.
I added all of my symbols and wired up the main parts of the USB hub. I'm going to use the PCM2902 for my DAC but the datasheet is really confusing so I haven't wired it up yet. It took a while to figure out how the cc pins should be connected for the usb ports, but I have figured out that the outputs should be using 56k ohm resistors pulled to 5v for a default power output of 500 mA.
I have just realized while taking this screenshot that I accidentally pulled the cc pins to gnd instead of 5v.
And now that is fixed. Next I need to connect the DAC but I think I understand most of how it should work.
Person20020 (Koji) 🚀
started USB Hub + DAC ago
12/2/2025 - Made Schematic Part 1
I had previously started to build a USB hub but I never finished and I decided to just start from scratch.
I added all of my symbols and wired up the main parts of the USB hub. I'm going to use the PCM2902 for my DAC but the datasheet is really confusing so I haven't wired it up yet. It took a while to figure out how the cc pins should be connected for the usb ports, but I have figured out that the outputs should be using 56k ohm resistors pulled to 5v for a default power output of 500 mA.
I have just realized while taking this screenshot that I accidentally pulled the cc pins to gnd instead of 5v.
And now that is fixed. Next I need to connect the DAC but I think I understand most of how it should work.
12/3/2025 - Finished Schematic
I finished drawing out the schematic. On the PCM2902 I decided to only connect the mute button as I prefer to control volume through my keyboard. The mute button probably won't be used very often but it shouldn't get in the way either.
12/5/2025 12 PM - Routed PCB Pt 1
I routed the USB hub part. I haven't worked on the dac section yet but I have just now realized that some of the capacitors are supposed to be polarized and need to be larger electrolytic caps.
I did use some vias on my usb lines but it is only usb 2.0 so it should be fine.. (I think it can handle like 10cm or something)
12/5/2025 5 PM - Routed PCB Pt 2
I finished routing the PCB and had to make a few changes. First changing mono input to stereo for the mic seemed somewhat complicated so I decided to get rid of mic in. I also fixed the capacitors by moving to larger aluminum ones.
I added some mounting holes to mount to the case. I think I'll use some printed standoffs with m2 heat set inserts to mount it so I chose spots that have space around them to place the screw holes.
It seems like I somehow managed to get it to be 5mm smaller in each direction than the last attempt that I made at this.
12/5/2025 6 PM - Designed case
I exported the PCB and now have finished the case. Right now it is pretty simple so I might go back and add more to it before I print it. I added a bending button to the top for the mute button. This keeps it much thinner than the last attempt I made which used a large 12mm push button.
12/10/2025 - Fixed case and added BOM
I fixed the case by adding a wider area around the USB ports + 3.5mm jack so that cables overmold would be able to fit. I also added everything to the BOM.