5G Base Station BBU + AAU Reference Design
An illustrative 5G base station reference design for the aggregation / edge layer of the five-layer network architecture, centered on the BBU baseband / transport board: 12 × 25G SFP28 eCPRI fronthaul ports connect over fiber to the AAU of each sector, 2 × 25G SFP28 backhaul ports uplink to the transport network, with GPS / BeiDou timing, a local maintenance Ethernet port and a Console port; −48V DC power is isolated and converted to 12V by a planar transformer. On the AAU side, the 25G fronthaul optical ports and the −48V power inlet protection follow the same selection as this page. Each position is marked with the VOOHU parts available, recommended part numbers and package pinouts.
Illustrative PCB ⇄ Schematic
Illustrative top-side view arranged by functional zone (not the actual layout). Red numbered dots mark positions VOOHU can supply. Click a component on the board, an entry in the index below or a part in the schematic to see recommended parts and package pinouts on the right.
Illustrative fronthaul port topology: the baseband SoC's 25G SerDes transmit / receive pairs connect through AC-coupling capacitors (fitted as the SerDes requires; the modules are AC-coupled internally) to TD± / RD± of the SFP28 2×6 cage + connector assembly (J1) (same pinout as SFP+); with 25G optical modules inserted, they link over fiber to the AAU of each sector (eCPRI). The control and status lines connect to the SoC's I²C / GPIO (the 12 ports are expanded through an I²C multiplexer), and each module's VccT / VccR are filtered from +3V3 by a VOOHU molded inductor and bypass capacitors, one per port. The AAU-side fronthaul ports have the same structure. Each pair is drawn as one line; coupling capacitors are drawn as symbols without values.
Board bill of materials
Summarized by position; click any row to locate it on the board above.
| No. | Zone | Position | Ref. | VOOHU category | Recommended part | Availability |
|---|---|---|---|---|---|---|
| 01 | A Fronthaul optical ports (to AAU) | Fronthaul SFP28 2×6 integrated cage + connector | J1 | SFP28 Series | WHSFP32126F002 | VOOHU |
| 02 | A Fronthaul optical ports (to AAU) | Fronthaul module supply filter inductors ×12 | L1 L2 L3 L4 L5 L6 | Molded Inductors | WHYTA0420 series | VOOHU |
| 03 | B Backhaul / timing | Backhaul SFP28 1×2 cage + 25G connector | J2 J3 | SFP28 Series | WHSFP30412W009 | VOOHU |
| 04 | B Backhaul / timing | Backhaul module supply filter inductors ×2 | L7 L8 | Molded Inductors | WHYTA0420 series | VOOHU |
| 05 | B Backhaul / timing | GPS / BeiDou antenna connector | J6 | — | — | Non-VOOHU |
| 06 | B Backhaul / timing | GPS / BeiDou timing module | U6 | — | — | Non-VOOHU |
| 07 | D Baseband processing | Baseband / transport SoC | U1 | — | — | Non-VOOHU |
| 08 | D Baseband processing | DDR memory | U2 | — | — | Non-VOOHU |
| 09 | D Baseband processing | Flash | U3 | — | — | Non-VOOHU |
| 10 | C Maintenance port | Maintenance port RJ45 with integrated magnetics | J4 | RJ45 with Integrated Magnetics | SYT211Q066CD2A4D | VOOHU |
| 11 | C Maintenance port | Maintenance port Gigabit PHY | U4 | Ethernet PHY | JL2101C-NI | VOOHU |
| 12 | C Maintenance port | Console RJ45 | J5 | RJ45 Connector | WH56A11810011101 | VOOHU |
| 13 | C Maintenance port | RS-232 level shifter | U5 | — | — | Non-VOOHU |
| 14 | E −48V power | −48V power input terminals (A / B dual feeds) | J7 | — | — | Non-VOOHU |
| 15 | E −48V power | Bidirectional input TVS | D1 | TVS ESD | WHTB058VA | VOOHU |
| 16 | E −48V power | Input varistor (MOV) | RV1 | MOV | WHM0082VA | VOOHU |
| 17 | E −48V power | Power-line common-mode choke (EMI) | L9 | Power Line Common Mode Chokes | WHAL-9070A-301T0 | VOOHU |
| 18 | E −48V power | Isolated DC-DC controller | U7 | — | — | Non-VOOHU |
| 19 | E −48V power | Planar transformer (48V → 12V isolated) | T1 | Planar Transformers | WHPT-EQ200-025 | VOOHU |
| 20 | E −48V power | Synchronous buck ×2 | U8 U9 | — | — | Non-VOOHU |
| 21 | E −48V power | Molded inductors ×2 (DC-DC) | L10 L11 | Molded Inductors | WHYT0630 Series | VOOHU |
| 22 | E −48V power | Multiphase controller + DrMOS | U10 | — | — | Non-VOOHU |
| 23 | E −48V power | Combined inductors ×2 (multiphase VR) | L12 L13 | Combined Inductors | WHPBU-100710N-R15L0 | VOOHU |
Resources & downloads
Board bill of materials
Reference designators, zones, VOOHU categories, recommended parts and availability for all 23 positions. Opens directly in Excel.
Datasheet collection
Datasheet PDFs for the VOOHU parts recommended on this board.
Design files & footprint library
Schematic, PCB, and VOOHU part footprints and 3D models.
Coming soonRequest the 5G base station BBU + AAU reference design full package
Includes the full-board position list, datasheets for the recommended VOOHU parts and position-by-position selection notes. For selection advice on your fronthaul port count and speed (10G / 25G), AAU-side optical ports and power inlet, or −48V power scheme, describe them in your requirements. We reply within 24 hours on business days.
