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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Preliminary Power Budget — Linux Cyberdeck
Status
Updated from the user's confirmed decisions. Architecture-level power decisions are closed; final regulator validation still requires datasheet checks during schematic design.
Confirmed Battery Pack
Table
| Parameter | Selection |
|---|---|
| Configuration | 1S2P, two pouch cells in parallel |
| Cells | 2x BatterySpace PL-5467100-2C |
| Cell rating | 4250 mAh, 3.7 V, 8.5 A / 2C max discharge each |
| Protection | Tenergy PCM P/N 32190 |
| PCM rating | 6 A working, 11 ± 2 A cutoff, 10K NTC B3435 |
| Pack capacity | 8500 mAh / ~31.5 Wh nominal |
| Usable energy | ~26–27 Wh after conversion |
| Runtime estimate | ~3.3 h at 8 W, ~2.2 h at 12 W |
| Nominal stack | 101.5 x 67.5 x 11.6 mm |
| Battery bay | Design for ~14–15 mm including tolerance/swell headroom |
| Connector | Molex Micro-Fit 3.0, 3-pos: B+, B-, NTC |
| Leads | >=20 AWG |
Confirmed Power Architecture
Diagram
Preliminary Load Assumptions
Table
| Subsystem | Rail | Typical Estimate | Peak Estimate | Notes |
|---|---|---|---|---|
| Raspberry Pi CM5 SC1598 / CM5108000 | 5 V | TBD by workload | up to 2.5 A module peak target | 8 GB Lite wireless CM5 |
| Waveshare 6.25inch DSI LCD (B) | 5 V | 400 mA typical | budget 1 A | Max published as TBD; 400 mA required for startup |
| SIM7600G-H-M.2 LTE/GNSS | 3.9 V | 0.1–0.8 A | ~2 A burst | Dedicated TPS63020 rail and local bulk capacitance required |
| RP2040-LoRa board | 3.3 V / USB | 50–150 mA | 300 mA | HF 850–930 MHz variant |
| Keyboard RP2040 + QMK | 3.3 V / USB | 20–100 mA | 200 mA | No backlight in rev 1; optional LED stuffing footprints |
| USB-A downstream VBUS | 5 V | 0–900 mA | 900 mA | TPS2553 current-limited switch |
| USB2514B hub + logic | 3.3 V / 5 V | 50–200 mA | 300 mA | Internal USB 2.0 hub |
| Speaker amplifier | 5 V | 100–500 mA | 1 A+ | MAX98357A, mono 8 ohm speaker |
| LEDs, IMU, RTC, debug | 3.3 V / VBAT | 20–100 mA | 200 mA | Miscellaneous allowance |
Preliminary System Power Ranges
Table
| Operating State | Estimated Power |
|---|---|
| Idle Linux, radios mostly idle, display low brightness | 6–8 W |
| Typical interactive use | 8–12 W |
| Heavy use with LTE bursts, bright display, USB-A load, speaker | 15–22 W transient |
Confirmed IC Selections
- PD sink: TPS25730D.
- Charger: BQ25792.
- 5 V boost: TPS61288.
- LTE rail: TPS63020 at 3.9 V.
- 3.3 V rail: TLV62569.
- USB hub: USB2514B.
- Fuel gauge: MAX17048.
- Battery protection: XB8886A pending OCP check, fallback BQ29700 + FET pair.
- USB-A VBUS: TPS2553.
- ESD candidates: TPD4E05U06 / USBLC6-2SC6 / TPD4E02B04.
Critical Checks During Schematic Review
- Confirm BQ25792 1S charging configuration, thermal limits, and 3–4 A charge-current feasibility.
- Confirm TPS61288 5 V boost thermal and inductor sizing at CM5/display/USB peak load.
- Confirm TPS63020 supports SIM7600 burst current at 3.9 V with adequate bulk capacitance.
- Confirm battery PCM and board-side eFuse/PTC coordination.
- Confirm USB-C PD sink current negotiation and no backfeed into VBUS.
- Confirm all battery temperature/NTC and fuel-gauge connections.
Status
Confirmed Battery Pack
Confirmed Power Architecture
Preliminary Load Assumptions
Preliminary System Power Ranges
Confirmed IC Selections
Critical Checks During Schematic Review
