Linux Cyberdeck Design
Thought for 41 sec
There’s still a moderate amount left before this is a full manufacturable board. The first-pass schematic is started, but we are not ready for PCB layout/manufacturing yet.
Main things still left to figure out
-
Display connection
- Exact Waveshare 6.25" DSI LCD-B connector pinout
- DSI lane count
- Backlight power/current
- Touch interface, if any
- Correct FPC connector part
-
Battery and power
- Exact 10,000 mAh battery pack
- Battery connector/current rating
- Battery protection/NTC details
- Confirm charger settings for that pack
- Validate 5 V boost converter can handle CM5 + LTE + display + USB-A peaks
-
Protection parts
- USB-C ESD protection
- USB-A USB 3.0 ESD protection
- HDMI ESD protection
- SIM card ESD protection
- Possibly battery/input fuse or protection
-
Regulator final values
- Final inductor part numbers
- Capacitor voltage/package choices
- TPS61288 compensation check
- Thermal/current margin check
- Layout-sensitive switching-node constraints
-
CM5 details
- Decide whether to add RTC backup for CM5 VBAT
- Decide whether to expose nRPIBOOT/service pads
- Confirm GPIO assignments for LTE, audio, IMU, keyboard wake
-
LTE/SIM7600 details
- Confirm exact SIM7600G-H-M.2 hardware guide handling for VDD_AUX and VDD_1V8
- Confirm LTE/GNSS antenna connector placement strategy
- Add SIM ESD
- Add RF/layout keepout rules
-
Keyboard board
- Main-board FPC is planned, but keyboard PCB itself still needs to be designed
- Need switch/keycap sourcing
- Need keyboard RP2040 schematic/firmware pin map finalized
-
Mechanical basics
- Rough board size
- Port locations
- Battery location
- Screen/keyboard placement constraints
- Mounting holes
- Antenna placement/keepouts
-
PCB layout setup
- Stackup choice, likely 6-layer because of USB 3.0, HDMI, MIPI DSI, RF, and power density
- Controlled-impedance rules
- Differential-pair rules
- Power trace/current rules
- Thermal copper areas
-
Bring-up and manufacturing prep
- Test pads
- Debug headers
- Board bring-up checklist
- BOM cleanup
- Footprint review
- DRC
- Gerbers/BOM/pick-and-place
Schematic is roughly 55–65% figured out.
Full board readiness is more like 30–40% complete, because layout, power validation, protection, display details, and mechanical constraints are still significant.
The biggest blockers are:
- Exact display connector/pinout
- Exact battery pack
- Power validation for the 5 V rail
- ESD/protection parts
- Mechanical board size/port placement
- Keyboard PCB design
Once those are decided, the remaining work becomes much more straightforward.
Power, display, protection
Find display pinout
Validate power rail
Add protection parts
Add test pads
Review battery connector
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Ask about this doc
Source Notes — Linux Cyberdeck
SIM7600G-H-M.2 / SIM7600X-H-M2
Sources checked:
- SIMCom SIM7600X-H-M2 product page.
- SIM7600X-M2 Hardware Design V1.01 PDF via Waveshare mirror.
Extracted design-relevant facts:
- LTE Cat-4 module family with M.2 form factor.
- Module dimensions listed: 42.0 x 31.4 x 3.8 mm.
- Supply range listed: 3.3–4.2 V.
- USB host interface supported for Linux/Android/Windows drivers and firmware upgrade.
- SIM interface supports 1.8 V / 3.0 V SIM card.
- GNSS supported on SIM7600G-H-M2 family.
- Exposed/support interfaces include UART, USB, optional PCM, LED, WoWWAN, W_DISABLE, I2C, and diversity receiver.
- Hardware design guidance indicates 2 A-class burst current support, low-impedance supply path, large low-ESR bulk capacitance near the module, and USB D+/D- as a 90 ohm differential pair.
- SIM card lines require short routing and ESD protection near the SIM socket.
- Cellular/GNSS RF paths require 50 ohm controlled impedance, antenna matching footprints, ground stitching, and antenna keepouts.
Sources checked:
- Waveshare RP2040-LoRa product page.
- Waveshare RP2040-LoRa wiki.
Extracted design-relevant facts:
- Board dimensions: 21.00 x 41.00 mm.
- Uses RP2040 and SX1262.
- Frequency variants:
- LF: 410–525 MHz.
- HF: 850–930 MHz.
- Antenna connector: onboard IPEX with IPEX-to-SMA adapter cable.
- Up to 20 multi-function GPIO pins.
- USB 1.1 device/host support.
- Onboard FPC 8-pin connector can adapt to USB Type-C via adapter board.
- SX1262 mapping found:
- DIO1: RP2040 GP16
- RST: GP23
- MISO: GP24
- MOSI: GP15
- CLK/SCK: GP14
- CS: GP13
- BUSY: GP18
- ANT_SW: GP17
- SX1262 SPI bus frequency should be less than 18 MHz.
Screen / Keyboard Assembly
Sources checked:
- User-supplied AliExpress URL and short URL.
- Search by AliExpress item/product clues.
- WhatGeek and MechKeys AJAZZ AKP846 pages.
Findings:
- User-supplied AliExpress page returned a 404 or incomplete page content through the web scraper.
- Short link did not expose product details.
- Search results strongly suggest the product may be an AJAZZ AKP846 10.1 inch smart display mechanical keyboard.
- Candidate product facts from third-party pages:
- 10.1 inch color touchscreen / secondary display.
- QMK/VIA programmable wired mechanical keyboard.
- 84-key layout with knob.
- Mirror/extended/share display modes mentioned.
- Candidate dimensions from MechKeys: 371 x 219 x 21 mm, 950 g.
- WhatGeek warns original wires are required for the screen function and third-party wires may not work.
- Unconfirmed: display resolution, electrical display interface, cable pinout, power input, touch interface, and Linux driver requirements.
RK3588S2 / Compute Platform
Sources checked:
- Rockchip RK3588S2 datasheet search results.
- Khadas Edge2 pages and docs search results.
- RK3588/RK3588S SOM search results including Radxa CM5 and other SOM vendors.
Findings:
- RK3588S2 supports high-performance Linux-class compute, but a raw SoC + LPDDR4x board is high complexity.
- Khadas Edge2 is an RK3588S2-class SBC option with 8 GB / 16 GB LPDDR4x variants according to search results.
- Radxa CM5 and other RK3588/RK3588S SOMs appear to be practical module options, though not necessarily exact RK3588S2.
- A user decision is required on whether exact RK3588S2 silicon is mandatory or whether RK3588/RK3588S module options are acceptable.
Superseded direction: user selected Raspberry Pi Compute Module 5 instead of RK3588-class SOM for the carrier design.
Raspberry Pi Compute Module 5
Source checked:
- User-attached
cm5-datasheet.pdf.
Extracted design-relevant facts:
- CM5 variants: 2 GB, 4 GB, 8 GB, or 16 GB LPDDR4x-4267; eMMC options 16/32/64 GB; Lite variant has no eMMC and exposes SDIO 2.0.
- Optional wireless variants include certified dual-band Wi-Fi and Bluetooth 5.0/BLE.
- Main input is 5 V on pins 77, 79, 81, 83, and 85; range 4.75–5.25 V.
- Power design should support up to 2.5 A peak CM5 module consumption.
- CM5_3.3V output is limited to 600 mA total and should not be used as a general system rail.
- GPIO_VREF must be tied to CM5_3.3V for 3.3 V GPIO or CM5_1.8V for 1.8 V GPIO; it must not float.
- CM5 exposes one USB 2.0 high-speed port and two USB 3.0 SuperSpeed ports.
- CM5 supports two HDMI 2.0 outputs and two 4-lane MIPI DSI/CSI-capable interfaces.
- CM5 supports up to three simultaneous displays across HDMI/DSI/DPI.
- PCIe is Gen 2 x1; PCIe RX needs external AC-coupling capacitors, TX AC coupling is included on CM5.
- Ethernet PHY is integrated; route differential pairs to a transformer or MagJack if Ethernet is used.
- Module size is 55 mm x 40 mm and uses two 100-pin high-density connectors.
- Carrier connector options include Amphenol 10164227-1001A1RLF and 10164227-1004A1RLF for different stack heights.
- HDMI and MIPI require 100 ohm differential routing and intra-pair length matching within 0.15 mm.
M5Stack CardKB / CardKB v1.1
Sources checked:
- M5Stack Unit CardKB product documentation.
- M5Stack Unit CardKB v1.1 product documentation.
- M5Stack CardKB v1.1 PDF resource.
Extracted design-relevant facts:
- Interface: I2C.
- I2C address: 0x5F.
- Connector: HY2.0-4P / Grove-style interface.
- Pinout: GND, 5V, SDA, SCL.
- Supply: 5 V.
- Approximate current from PDF resource: 20 mA.
- Controller varies by source/revision: ATMega8A listed on v1.1 page; MEGA328P/ATmega328P-AU listed in PDF resource.
- Dimensions vary by source/revision: 88.0 x 54.0 x 5.0 mm on page; 84 x 54 x 5 mm in PDF resource.
- Key count varies by source/revision: 50 keys on page; 56 keys in PDF resource.
Sources checked:
- Waveshare 6.25inch DSI LCD (B) product page.
- Waveshare 6.25inch DSI LCD wiki.
Extracted design-relevant facts:
- Product: 6.25inch DSI LCD (B), SKU 35000.
- Resolution: 720 x 1560.
- Display interface: Raspberry Pi-style MIPI DSI.
- Pinout indicates two DSI data lanes plus clock pair.
- Touch: 5-point capacitive touch over I2C; Goodix touchscreen appears as
10-0014 Goodix Capacitive TouchScreen. - Power: 5 V via pogo/spring pins or PH2.0 cable depending host; 3.3 V pins present on the DSI interface.
- Interface pinout from wiki: 1 GND, 2 DSI1_DN1, 3 DSI1_DP1, 4 GND, 5 DSI1_CN, 6 DSI1_CP, 7 GND, 8 DSI1_DN0, 9 DSI1_DP0, 10 GND, 11 SCL0, 12 SDA0, 13 GND, 14 3V3, 15 3V3.
- Raspberry Pi overlay:
vc4-kms-dsi-waveshare-panel,6_25_inch. - Risk: documented primarily for Raspberry Pi; RK3588-class SOM support depends on SOM DSI lane availability, connector mapping, and Linux device-tree/panel driver support.
SIM7600G-H-M.2 / SIM7600X-H-M2
Waveshare RP2040-LoRa
Screen / Keyboard Assembly
RK3588S2 / Compute Platform
Raspberry Pi Compute Module 5
M5Stack CardKB / CardKB v1.1
Waveshare 6.25inch DSI LCD (B)
