COM-HPC Carrier Layout
Thought for 15 sec
I’ll update Version 5.0 front-view visuals only so the Compute Module is drawn with correct 90 mm × 100 mm proportions and occupies the appropriate larger area. Version 4.0 stays locked.
Worked for 3 mins 46 sec
Thought for 26 sec
Created image.
You can move the component labels off to the side of the PCB
Worked for 4 mins 54 sec
Redone for Tiny Tim Version 5.0 front view.
Changes applied:
- Compute Module is shown much larger with intended 90 mm × 100 mm proportions.
- Carrier board remains 105 mm × 115 mm.
- Labels moved off the PCB as side callouts to reduce clutter.
- Version 4.0 remains locked and unchanged.
Updated file:
Updated Front View
Image
Redo rear and review
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Tiny Tim Version 4.0 Power Budget
Lock Notice
Tiny Tim Version 4.0 is locked. This power budget is frozen as part of Tiny Tim Version 4.0 Locked Export Package.
Scope and Status
This is the Version 4.0 system power budget for the Tiny Tim COM-HPC Mini type carrier concept.
PoE design work is stopped per user instruction. PoE-related calculations below are retained only as historical feasibility analysis and must not be implemented unless the user explicitly reopens PoE design.
Status: preliminary engineering budget. It is complete enough to guide power-source architecture, but not final enough to size production regulators/fuses because the exact COM-HPC Mini module, endpoint devices, and user power limits are not yet locked.
No schematic, layout, image geometry, connector placement, or board dimensions were changed while creating this budget.
Key Conclusion
Use a dedicated high-current non-PoE primary power input for Version 4.0.
The prior PoE analysis showed PoE was insufficient for full operation, and the user has now stopped all PoE design work.
The selected PoE path, Bel G55-122N-155 + TI TPS2373-3, is appropriate for an IEEE 802.3bt Type 3 / 60 W PSE-class input. Planning limit is approximately:
- ~51 W at the PoE PD input after cable loss
- ~45 W available at 12 V after an assumed 90% isolated DC/DC conversion
- ~3.75 A at 12 V available from PoE-derived 12 V
That is enough for a limited/service configuration, but not enough for a full carrier with a high-performance COM-HPC Mini module, rear M.2 modules, powered USB/TBT ports, cameras, GMSL, fan, and auxiliary headers.
Design Power Cases
Table
| Case | Description | Estimated System Load | 12 V Current Equivalent | PoE Viable? |
|---|---|---|---|---|
| PoE service mode | Module power-limited, minimal peripherals, no high external port power | ~33 W | ~2.8 A | Yes |
| Nominal active system | Typical COM-HPC Mini load plus common peripherals | ~104 W | ~8.7 A | No |
| Peak/turbo system | Module turbo plus powered ports/peripherals | ~225 W | ~18.8 A | No |
| Standard-level worst module case | Uses 107 W module ceiling plus peak peripherals | ~242 W | ~20.2 A | No |
COM-HPC Mini Module Power Basis
Public COM-HPC Mini references show a wide spread:
Table
| Source / Basis | Power Figure | Notes |
|---|---|---|
| PICMG / COM-HPC standard-level discussion | up to 107 W input power | Wide-range 8 V case; connector/module limits apply. |
| congatec COM-HPC Mini guidance | up to 76 W | Practical Mini target cited publicly. |
| TQ TQMxCU1-HPCM | typ. 10-35 W / max. 78 W | Product-level preliminary data. |
| TQ detailed manual examples | ~4.5 W idle, 16-34 W max load, 67-87 W turbo peak | Turbo peak under 28 seconds; useful for power-supply design. |
| AAEON / Acrosser examples | ~4.13 A at 12 V typical, ~49.6 W | Specific COM-HPC Mini module examples. |
Budget choice for Tiny Tim Version 4.0:
- PoE service-mode module assumption: 25 W
- Nominal module assumption: 50 W
- Peak module assumption: 90 W
- Worst-case module ceiling: 107 W
Load Enumeration by Function
Assumed primary intermediate rail: 12 V system rail. Downstream 5 V / 3.3 V rails are reflected back to equivalent system input power.
Table
| Load Group | Quantity | Typical / Nominal Power | Peak / Design Power | Notes |
|---|---|---|---|---|
| COM-HPC Mini module | 1 | 50 W | 90 W turbo / 107 W ceiling | Exact module TBD. |
| M.2 M/B-key 2280 NVMe | 1 | 4 W | 8 W | From 3.3 V M.2 rail; depends on SSD. |
| M.2 E/B-key 2230 wireless | 1 | 2 W | 5 W | Wi-Fi/BT or similar; depends on module. |
| Rear M.2 Wireless SDR / PCIe USB | 1 | 5 W | 10 W | Placeholder until actual SDR card is known. |
| USB-A host downstream power | 3 | 4.5 W | 13.5 W | Peak assumes 3x 5 V / 900 mA USB 3.x sourcing. |
| USB-C OTG downstream power | 3 | 7.5 W | 22.5 W | Peak assumes capped 5 V / 1.5 A per port. Higher USB-C sourcing would exceed this budget. |
| Type-C TBT downstream power | 1 | 5 W | 15 W | Placeholder; TBT/USB4 power role TBD. |
| HDMI 5 V output | 1 | 0.3 W | 0.5 W | HDMI source 5 V detect/power allowance. |
| CSI camera FFC | 3 | 4.5 W | 7.5 W | Assumes 1.5 W typical / 2.5 W peak per camera. |
| GMSL / Fakra camera power | 4 | 8 W | 16 W | Assumes remote camera or serializer support power; exact architecture TBD. |
| Fan | 1 | 3 W | 6 W | 12 V fan estimate. |
| 10GbE PHY / support circuits | 2 | 4 W | 6 W | If PHYs are on carrier; exact COM-HPC module interface TBD. |
| JST-GH auxiliary external loads | 11 | 5 W | 15 W | Must be capped by design. Connector ratings are not a power budget. |
| Carrier logic / LEDs / converters overhead | n/a | 5 W | 10 W | Supervisors, level shifting, USB/TBT support, losses. |
Summed Power Cases
1. PoE Service Mode
Assumes:
- COM-HPC Mini module is power-limited to ~25 W.
- Only one 10GbE/PoE port active.
- M.2 modules and high-power USB/TBT sourcing are disabled or limited.
- Camera/GMSL loads off or limited.
- Fan and carrier logic active.
Table
| Load | Power |
|---|---|
| COM-HPC Mini module service limit | 25 W |
| 10GbE support / MagJack / PHY allowance | 3 W |
| Fan low/medium | 2 W |
| Carrier logic and conversion overhead | 3 W |
| Total | 33 W |
| Equivalent at 12 V | 2.75 A |
| PoE 12 V budget available | ~45 W / 3.75 A |
| Margin | ~12 W |
Result: PoE service mode is feasible.
2. Nominal Active System
Table
| Load | Power |
|---|---|
| COM-HPC Mini module nominal | 50 W |
| M.2 M-key 2280 | 4 W |
| M.2 E-key 2230 | 2 W |
| Rear PCIe/SDR | 5 W |
| USB-A host power | 4.5 W |
| USB-C OTG power | 7.5 W |
| Type-C TBT placeholder | 5 W |
| HDMI | 0.3 W |
| CSI cameras | 4.5 W |
| GMSL/Fakra cameras | 8 W |
| Fan | 3 W |
| 10GbE support | 4 W |
| JST-GH auxiliary loads | 5 W |
| Carrier logic / losses | 5 W |
| Total | ~108 W |
| Equivalent at 12 V | ~9.0 A |
Result: PoE is not sufficient for nominal full-system operation. A dedicated 12 V input should be sized for at least this class of load plus margin.
3. Peak / Turbo System
Table
| Load | Power |
|---|---|
| COM-HPC Mini module turbo | 90 W |
| M.2 M-key 2280 | 8 W |
| M.2 E-key 2230 | 5 W |
| Rear PCIe/SDR | 10 W |
| USB-A host power | 13.5 W |
| USB-C OTG power | 22.5 W |
| Type-C TBT power | 15 W |
| HDMI | 0.5 W |
| CSI cameras | 7.5 W |
| GMSL/Fakra cameras | 16 W |
| Fan | 6 W |
| 10GbE support | 6 W |
| JST-GH auxiliary loads | 15 W |
| Carrier logic / losses | 10 W |
| Total | ~225 W |
| Equivalent at 12 V | ~18.8 A |
Result: Peak unrestricted system load is far beyond PoE. If this use case is required, the carrier should use a high-current dedicated input and strict thermal design.
4. Standard-Level Worst Module Ceiling
Same as Peak/Turbo case, but using 107 W for the COM-HPC Mini module instead of 90 W:
Table
| Item | Power |
|---|---|
| Peak system with 90 W module | 225 W |
| Module delta to 107 W | +17 W |
| Total | ~242 W |
| Equivalent at 12 V | ~20.2 A |
Result: If designing to the standard-level module ceiling and external port peaks, size the main power input near a 250 W class budget before margin.
Input Source Implications
PoE Input — Discontinued / Do Not Implement
Table
| Parameter | Planning Value |
|---|---|
| PoE standard target | IEEE 802.3bt Type 3 / 60 W PSE |
| PD input planning power | ~51 W |
| 12 V output after 90% conversion | ~45 W |
| 12 V current | ~3.75 A |
| Recommended use | Do not implement; historical analysis only |
Dedicated 12 V Input
Table
| Use Case | Minimum 12 V Current | With 25% Margin | Recommendation |
|---|---|---|---|
| Nominal full system, ~108 W | ~9.0 A | ~11.3 A | 12 V / 12 A minimum practical input |
| Peak/turbo unrestricted, ~225 W | ~18.8 A | ~23.5 A | 12 V / 25 A class input |
| Worst module ceiling + peak peripherals, ~242 W | ~20.2 A | ~25.3 A | 12 V / 25-30 A class input |
Finalized Version 4.0 12 V Input Connector Policy
Version 4.0 primary non-PoE input connector is now:
J_12VIN1 = AMASS XT60PW-M
Schematic nets created:
Table
| Connector Pin | Net |
|---|---|
| J_12VIN1:Pos | 12V_IN |
| J_12VIN1:Neg | PGND |
Policy:
- Use
J_12VIN1as the main 12 V input. - Design target: 12 V / 12 A minimum nominal, 25 A class peak/unrestricted.
- Treat the earlier CLIK-Mate 5 V input row as low-current/service/auxiliary only unless explicitly redesigned.
- Validate XT60 footprint, copper, thermal relief, fuse/ideal-diode current, and wire gauge before layout release.
5 V IN Connector Issue
The current v2.0 table labels a 5V IN redundant power connector. Based on this budget, a 5 V primary input is not recommended for full-system operation unless it is very high current.
Examples:
Table
| System Power | 5 V Input Current before losses | Practical Concern |
|---|---|---|
| 45 W | 9 A | Already high for small wire-to-board connectors. |
| 108 W | 21.6 A | Impractical for CLIK-Mate class connector. |
| 225 W | 45 A | Not appropriate. |
Recommendation implemented for Version 4.0: main external input strategy is 12 V primary input via XT60 unless the final module explicitly requires a different input architecture.
Required Power Policy Decisions
- PoE role: service/backup only vs primary limited-power input.
- Main input voltage: recommend 12 V primary input, not 5 V, for full carrier operation.
- External port power caps: define maximum source current for each USB-A, USB-C, TBT, JST-GH, CSI, and GMSL connector.
- M.2 power limits: define whether rear M.2 M-key supports high-power NVMe modules and whether M.2 E-key/SDR can be power-limited.
- Thermal target: decide whether the board must survive peak/turbo with all ports powered, or only nominal sustained load.
Recommended Version 4.0 Power Architecture
Diagram
Final Recommendation
- Do not implement PoE in Version 4.0 unless the user explicitly reopens PoE design later.
- Use 12 V primary input sized for at least 12 A for nominal operation, and 25 A class if peak/turbo unrestricted operation is required.
- Do not finalize fuses, ideal diodes, regulators, or connector current ratings until the exact COM-HPC Mini module and port-power policy are chosen.
Lock Notice
Scope and Status
Key Conclusion
Design Power Cases
COM-HPC Mini Module Power Basis
Load Enumeration by Function
Summed Power Cases
1. PoE Service Mode
2. Nominal Active System
3. Peak / Turbo System
4. Standard-Level Worst Module Ceiling
Input Source Implications
PoE Input — Discontinued / Do Not Implement
Dedicated 12 V Input
Finalized Version 4.0 12 V Input Connector Policy
5 V IN Connector Issue
Required Power Policy Decisions
Recommended Version 4.0 Power Architecture
Final Recommendation
