Hardware Spec - ReaverShadow/Mu-boo-Cub-Mug GitHub Wiki

Eletro-Mechanical (WIP)

Mechanical

  • SO-DIMM socket
  • M.2 Socket
  • Screw stand-offs + screws
  • battery socket (CR1220 3V)
  • Custom Design Enclosure, including housing for batteries.

Ports

  • 2x USB 4.0 Type-C OCuLink (See note in connectivity section)
  • 2x USB 3.2 Gen2 Type-C
  • 1x USB 2.0 Type-A (no promises, based on available PCB and mechanical space.)

Pinout

  • SoC-I2C
  • UART#1

Buttons

  • Power tact switch
  • "Button #2" Performance mode tact switch (Removed to simplify V1 design. Would like to see in a V2. Keep button for others to design with)

CPU PL1 limits (Not implemented in V1)

Table will be kept for reference

Performance Mode Battery USB-PD (12V/3A) USB-PD (12V/5A)
Default 6W 22W 35W
Unleashed 22W 30W TBD

Note 1: Headroom for board power draw needs to be considered. preliminary estimating 10W.

Note 2: Unleashing will likely cause fan to be high.

Note 3: PL2 numbers will need to be determined based on testing draw/thermals.

Note 4: According to official documentation, Lattepanda Mu/N100 has a TDP between 6-10W. testing would be needed to get a basis. Some reviews of N100 mini-pc, showed idle of 9W and workload of 22W.

Electrical (WIP)

LEDs

  • Power on

Storage

  • M.2 2230 NVMe SSD via HSIO2/3 (PCIe 3.0 x1, 1.97 GB/s, half the USB4 transfer rate as limited by the system )

Ideally PCIe x4 (HSIO0-3). If stuck with only a PCIe x2 port, an NVMe at x2 will still 4 times faster then SATA3 SSD, even if it's limited to it's full speed.

Connectivity

  • OCuLink USB 4 Controller Intel JHL8540 Maple Ridge via HSIO 8-11 (PCIe 3.0 x4) (due to limited availability of datasheets/chips to greater public, fall-back to OCuLink)

ASM4242 is an alternative, but doesn't seem available

  • 2x USB 3.2 Gen 2x1 for USB-PD (charging/powering) and Display Port/HDMI output.
  • M.2 E Key 2230 WLAN network card via HSIO6 (PCIe 3.0 x1, 0.985 GB/s)

Intel® Wi-Fi 6E AX210

  • There is a history of issues with Virtual Desktop when using Windows and Intel WiFi cards in AP mode. May need to use Broadcomm chipset.

Main Battery

(Based on N100 mini-pc review, 22W required while running The Witcher 3)

  • 4 x Standard 18650 Li-Ion cells (Each cell ranges from range for 2Ah to 3.5Ah).
  • Implement a USBHID-UPS method, via a ARM Cortex-M based MCU.

For future reference

4x Li-po (nominal 14V4), at approx 22W x 2.5Hours = 55Wh. Avg V = ( peak + discharged )/2 = ( 16V8 + 12V )/2 = 14V4. mAh = ( Energy (Wh) x 1000 )/ nominal V = 3819mAh. Add 1.2 efficiency losses, reliability and battery longevity = 3819mAh * 1.2 = approx 4500mAh.

Power

  • USB-PD IC
  • Buck converter. Aim for as self contained as possible, perhaps a module for V1. (Specially choose 14V8 nominal battery as to avoid using Boost, which are less efficient.)
  • Reverse Current and surge/over voltage protection
  • RTC Battery