COM Express NAS Carrier Board Design

1:49

Clarifying component-linking rules.

Structuring the POWER sheet.

Clarifying the POWER sheet details.

Focusing on component linking.

Preparing the POWER sheet output.

Finalizing component linking.

POWER sheet (completed)
Symbols and reference designators (placeholders)
Hierarchical ports (exact net names)
  • Rails/grounds: VBUS_HV, +5V_BACKPLANE, +3V3, COM_IN, +5V_USB, GND, CHASSIS_GND, CHASSIS_TO_GND_TIE
  • Control/status: EN_5V_BACKPLANE, EN_3V3, EN_NIC_RAILS, PGOOD_5V, PGOOD_3V3, PGOOD_COMIN, FAULT_PSU, PD_OK, PD_HIGH_POWER_OK, PD_DERATE, +5V_BP_SENSE, GND_BP_SENSE
Power-path wiring (logical)
  • J_USB_C.VBUS → D_TVS.A → U_HS.IN
  • U_HS.OUT → VBUS_HV (hierarchical port)
  • J_USB_C.CC1 ↔ U_PD.CC1 (direct local wire, no global net label)
  • J_USB_C.CC2 ↔ U_PD.CC2 (direct local wire, no global net label)
  • U_PD status outputs → PD_OK, PD_HIGH_POWER_OK, PD_DERATE (hierarchical ports)
  • U_HS.FAULT → FAULT_PSU (hierarchical port)
  • J_USB_C.SHELL → CHASSIS_GND
  • All device grounds (U_PD, U_HS, U_5V, U_3V3, U_COMIN if used, D_TVS cathode return) → GND
Regulators and rails (star from VBUS_HV)
  • VBUS_HV → U_5V.VIN; U_5V.VOUT → +5V_BACKPLANE
    • U_5V.EN ← EN_5V_BACKPLANE
    • U_5V.PGOOD → PGOOD_5V
  • VBUS_HV → U_3V3.VIN; U_3V3.VOUT → +3V3
    • U_3V3.EN ← EN_3V3
    • U_3V3.PGOOD → PGOOD_3V3
  • COM_IN selectable branch (populate only one):
    • Option A (buck): VBUS_HV → U_COMIN.VIN; U_COMIN.VOUT → COM_IN; U_COMIN.PGOOD → PGOOD_COMIN
    • Option B (pass-through): VBUS_HV → JP_COMIN → COM_IN; PGOOD_COMIN sourced from a generic “COM_IN_GOOD” placeholder on U_COMIN block
  • +5V_USB: exposed as a separate rail (hierarchical port), not tied to +5V_BACKPLANE on this sheet
Backplane sense (Rev-A ties)
  • +5V_BACKPLANE → R_TIE_P → TP_BP → +5V_BP_SENSE (hierarchical port)
  • GND → R_TIE_G → TP_BPG → GND_BP_SENSE (hierarchical port)
Chassis bonding (single point)
  • CHASSIS_GND ↔ X_TIE ↔ GND
  • Export CHASSIS_TO_GND_TIE (hierarchical port) at X_TIE to indicate intentional single bond location
Notes/constraints applied
  • USB-C is power-only; no D+/D- routing on this sheet.
  • VBUS chain: USB-C VBUS → TVS → Hot-swap/eFuse → VBUS_HV.
  • Star topology: VBUS_HV feeds 5V and 3.3V bucks, and the COM_IN option block.
  • +5V_USB is a distinct rail placeholder for rear I/O (USB-A, HDMI_5V_OUT via switch/fuse on REAR_IO), not tied to +5V_BACKPLANE.
  • CHASSIS_GND only bonds to GND through X_TIE; no other chassis–digital bonds on this sheet.
  • All enable/PGOOD/PD nets are exposed as hierarchical ports; generic resistors provided only as placeholders (no values).
Pull in from project
Library placeholders list
Net name audit
Chassis bond check
68 days



  • Ground
    A common return path for electric current. Commonly known as ground.
  • Net Portal
    Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
  • Power Net Portal
    Wirelessly connects power nets on schematic. Identical to the net portal, but with a power symbol. Used to organize schematics and separate functional blocks. To wirelessly connect power net portals, give them the same designator. #portal #power
  • Generic Resistor
    A generic fixed resistor ideal for rapid circuit topology development. Its footprint automatically adapts based on the selected package case code—supporting 0402, 0603, 0805, 1203, and many other standard SMD packages, as well as axial horizontal and vertical configurations. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0 ohm, 10 ohm, 100 ohm, 1.0k ohm, 10k ohm, 100k ohm, 1.0M ohm 1.1 ohm, 11 ohm, 110 ohm, 1.1k ohm, 11k ohm, 110k ohm, 1.1M ohm 1.2 ohm, 12 ohm, 120 ohm, 1.2k ohm, 12k ohm, 120k ohm, 1.2M ohm 1.3 ohm, 13 ohm, 130 ohm, 1.3k ohm, 13k ohm, 130k ohm, 1.3M ohm 1.5 ohm, 15 ohm, 150 ohm, 1.5k ohm, 15k ohm, 150k ohm, 1.5M ohm 1.6 ohm, 16 ohm, 160 ohm, 1.6k ohm, 16k ohm, 160k ohm, 1.6M ohm 1.8 ohm, 18 ohm, 180 ohm, 1.8K ohm, 18k ohm, 180k ohm, 1.8M ohm 2.0 ohm, 20 ohm, 200 ohm, 2.0k ohm, 20k ohm, 200k ohm, 2.0M ohm 2.2 ohm, 22 ohm, 220 ohm, 2.2k ohm, 22k ohm, 220k ohm, 2.2M ohm 2.4 ohm, 24 ohm, 240 ohm, 2.4k ohm, 24k ohm, 240k ohm, 2.4M ohm 2.7 ohm, 27 ohm, 270 ohm, 2.7k ohm, 27k ohm, 270k ohm, 2.7M ohm 3.0 ohm, 30 ohm, 300 ohm, 3.0K ohm, 30K ohm, 300K ohm, 3.0M ohm 3.3 ohm, 33 ohm, 330 ohm, 3.3k ohm, 33k ohm, 330k ohm, 3.3M ohm 3.6 ohm, 36 ohm, 360 ohm, 3.6k ohm, 36k ohm, 360k ohm, 3.6M ohm 3.9 ohm, 39 ohm, 390 ohm, 3.9k ohm, 39k ohm, 390k ohm, 3.9M ohm 4.3 ohm, 43 ohm, 430 ohm, 4.3k ohm, 43K ohm, 430K ohm, 4.3M ohm 4.7 ohm, 47 ohm, 470 ohm, 4.7k ohm, 47k ohm, 470k ohm, 4.7M ohm 5.1 ohm, 51 ohm, 510 ohm, 5.1k ohm, 51k ohm, 510k ohm, 5.1M ohm 5.6 ohm, 56 ohm, 560 ohm, 5.6k ohm, 56k ohm, 560k ohm, 5.6M ohm 6.2 ohm, 62 ohm, 620 ohm, 6.2k ohm, 62K ohm, 620K ohm, 6.2M ohm 6.8 ohm, 68 ohm, 680 ohm, 6.8k ohm, 68k ohm, 680k ohm, 6.8M ohm 7.5 ohm, 75 ohm, 750 ohm, 7.5k ohm, 75k ohm, 750k ohm, 7.5M ohm 8.2 ohm, 82 ohm, 820 ohm, 8.2k ohm, 82k ohm, 820k ohm, 8.2M ohm 9.1 ohm, 91 ohm, 910 ohm, 9.1k ohm, 91k ohm, 910k ohm, 9.1M ohm #generics #CommonPartsLibrary
  • Generic Capacitor
    A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF, 10pF, 100pF, 1000pF, 0.01uF, 0.1uF, 1.0uF, 10uF, 100uF, 1000uF, 10000uF 1.1pF, 11pF, 110pF, 1100pF 1.2pF, 12pF, 120pF, 1200pF 1.3pF, 13pF, 130pF, 1300pF 1.5pF, 15pF, 150pF, 1500pF, 0.015uF, 0.15uF, 1.5uF, 15uF, 150uF, 1500uF 1.6pF, 16pF, 160pF, 1600pF 1.8pF, 18pF, 180pF, 1800pF 2.0pF, 20pF, 200pF, 2000pF 2.2pF, 22pF, 220pF, 2200pF, 0.022uF, 0.22uF, 2.2uF, 22uF, 220uF, 2200uF 2.4pF, 24pF, 240pF, 2400pF 2.7pF, 27pF, 270pF, 2700pF 3.0pF, 30pF, 300pF, 3000pF 3.3pF, 33pF, 330pF, 3300pF, 0.033uF, 0.33uF, 3.3uF, 33uF, 330uF, 3300uF 3.6pF, 36pF, 360pF, 3600pF 3.9pF, 39pF, 390pF, 3900pF 4.3pF, 43pF, 430pF, 4300pF 4.7pF, 47pF, 470pF, 4700pF, 0.047uF, 0.47uF, 4.7uF, 47uF, 470uF, 4700uF 5.1pF, 51pF, 510pF, 5100pF 5.6pF, 56pF, 560pF, 5600pF 6.2pF, 62pF, 620pF, 6200pF 6.8pF, 68pF, 680pF, 6800pF, 0.068uF, 0.68uF, 6.8uF, 68uF, 680uF, 6800uF 7.5pF, 75pF, 750pF, 7500pF 8.2pF, 82pF, 820pF, 8200pF 9.1pF, 91pF, 910pF, 9100pF #generics #CommonPartsLibrary
  • Generic Inductor
    A generic fixed inductor suitable for rapid circuit topology development. The footprint automatically adapts based on the selected package, supporting standard SMD sizes (e.g., 0402, 0603, 0805) as well as well-known inductor packages such as SDR1806, PA4320, SRN6028, and SRR1260. Standard inductor values: 1.0 nH, 10 nH, 100 nH, 1.0 µH, 10 µH, 100 µH, 1.0 mH 1.2 nH, 12 nH, 120 nH, 1.2 µH, 12 µH, 120 µH, 1.2 mH 1.5 nH, 15 nH, 150 nH, 1.5 µH, 15 µH, 150 µH, 1.5 mH 1.8 nH, 18 nH, 180 nH, 1.8 µH, 18 µH, 180 µH, 1.8 mH 2.2 nH, 22 nH, 220 nH, 2.2 µH, 22 µH, 220 µH, 2.2 mH 2.7 nH, 27 nH, 270 nH, 2.7 µH, 27 µH, 270 µH, 2.7 mH 3.3 nH, 33 nH, 330 nH, 3.3 µH, 33 µH, 330 µH, 3.3 mH 3.9 nH, 39 nH, 390 nH, 3.9 µH, 39 µH, 390 µH, 3.9 mH 4.7 nH, 47 nH, 470 nH, 4.7 µH, 47 µH, 470 µH, 4.7 mH 5.6 nH, 56 nH, 560 nH, 5.6 µH, 56 µH, 560 µH, 5.6 mH 6.8 nH, 68 nH, 680 nH, 6.8 µH, 68 µH, 680 µH, 6.8 mH 8.2 nH, 82 nH, 820 nH, 8.2 µH, 82 µH, 820 µH, 8.2 mH #generics #CommonPartsLibrary
  • Terminal
    Terminal
    An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
  • RMCF0805JT47K0
    47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film #forLedBlink
  • 875105359001
    10uF Capacitor Aluminum Polymer 20% 16V SMD 5x5.3mm #forLedBlink #commonpartslibrary #capacitor #aluminumpolymer #radialcan
  • CTL1206FYW1T
    Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric) #forLedBlink

Specific Amber Dejarik

Specific Amber Dejarik thumbnail
COM Express Type 6 Compact NAS Carrier - Multi-sheet Schematic

Properties

HDMI, USB-A x2, 2.5GbE RJ45, 10GbE SFP+, USB-C PD

Vertical mount on left-chamber dividing wall; rear I/O facing back edge; cutout to right chamber for backplane cables.

Controlled impedance for PCIe Gen3, SATA 6G, HDMI TMDS; ground stitching around SFP+ cage; isolate 5V@12A power from high-speed region.

flowchart TD COM_MOD["COM Express Type 6 Compact"] -->|"PCIe Gen3 x4"| NIC10G["10GbE PCIe Endpoint"] NIC10G --> SFP["SFP+ Cage"] COM_MOD -->|"PCIe Gen3 x1"| NIC25G["2.5GbE PCIe NIC"] NIC25G --> RJ45["RJ45 Magjack"] COM_MOD -->|"PCIe Gen3 x2"| ASM["ASM1166"] ASM --> SASA["SFF-8643 Port A SATA0-3"] ASM --> SASB["SFF-8643 Port B SATA4-5"] COM_MOD -->|"PCIe Gen3 x1"| M2["M.2 E-key WiFi"] COM_MOD -->|"USB2"| USBA1["USB-A Port 1"] COM_MOD -->|"USB2"| USBA2["USB-A Port 2"] COM_MOD -->|"USB2"| BT["M.2 BT USB2"] COM_MOD -->|"HDMI"| HDMI["HDMI Connector"] USBC["USB-C PD In"] --> PD["PD Sink"] PD --> HOTSWAP["Hot-swap eFuse"] HOTSWAP --> VBUS_HV["VBUS_HV"] VBUS_HV --> BUCK5["5V Backplane"] VBUS_HV --> BUCK33["3V3"] VBUS_HV --> COMIN["COM_IN"] VBUS_HV --> NICRAILS["NIC Rails"]

Pricing & Availability

Distributor

Qty 1

Controls