EtherCAT Stepper Drive Reference Design
An illustrative EtherCAT two-phase stepper drive design for conveyor lines, dispensing / labeling machines, inspection equipment and multi-axis modules: DC 24 ~ 48V input, dual H-bridges driving a two-phase hybrid stepper motor, an EtherCAT dual-port slave (daisy-chain in / out), an incremental encoder interface for closed-loop control, optocoupler-isolated digital I/O (home / limit / alarm / brake) and a Type-C tuning port. Valve-island fieldbus nodes at the L0 field level use the same EtherCAT dual-port communication architecture. This page covers the function, selection notes and available VOOHU parts for 28 component positions.
Illustrative PCB ⇄ Schematic
The illustrative layout shows placement and component positions; click any position to see its selection notes, recommended parts and package. The board view is an illustration neatly arranged by functional zone (not the actual layout); the EtherCAT ports, encoder, I/O, tuning port and motor / power terminals sit along the bottom edge, and the stepper motor is an external node.
The EtherCAT IN and OUT ports are identical, so the diagram shows 1 port and 1 differential pair (the other 10/100 pair is the same). J1 is a dual RJ45 with integrated magnetics and common-mode chokes; the PHY-side pairs are clamped by ESD arrays D1 / D2 and go to the JL1111BI-NI (EtherCAT-version PHY), which connects over MII to the slave controller (ESC); the ESC connects to the stepper MCU over PDI. The communication part of a valve-island fieldbus node is the same as this chain. Center-tap wiring, termination and crystal load capacitor values per the PHY datasheet.
Board bill of materials
Click any row to jump to that position and view its selection notes
| No. | Zone | Position | Ref. | VOOHU category | Recommended part | Availability |
|---|---|---|---|---|---|---|
| 01 | A EtherCAT ports | Dual RJ45 (integrated magnetics, EtherCAT IN / OUT) | J1 | RJ45 Connectors | SYT212B579CD2A4D | VOOHU |
| 02 | A EtherCAT ports | Ethernet ESD array ×2 | D1 D2 | TVS / ESD | WHALD03G4U | VOOHU |
| 03 | A EtherCAT ports | EtherCAT 10/100 PHY ×2 | U1 U2 | Ethernet PHY | JL1111BI-NI | VOOHU |
| 04 | A EtherCAT ports | PHY 25MHz crystal | Y1 | — | — | Non-VOOHU |
| 05 | B Encoder | Encoder interface (incremental ABZ differential) | J2 | — | — | Non-VOOHU |
| 06 | B Encoder | Encoder ESD ×3 | D3 D4 D5 | TVS / ESD | WHALD30E2B | VOOHU |
| 07 | B Encoder | Encoder signal-line CMC ×3 | L1 L2 L3 | Signal Line CMC | WHAC-3225B-510U0 | VOOHU |
| 08 | B Encoder | RS-422 differential line receiver | U3 | — | — | Non-VOOHU |
| 09 | C I/O · Tuning | I/O terminal (home / limit / alarm / brake) | J3 | — | — | Non-VOOHU |
| 10 | C I/O · Tuning | I/O terminal TVS | D6 | TVS / ESD | WHALD30E2B | VOOHU |
| 11 | C I/O · Tuning | Digital I/O optocoupler | U4 | — | — | Non-VOOHU |
| 12 | C I/O · Tuning | USB Type-C tuning port (USB 2.0 only) | J4 | USB / Type-C | WHTCAX01167303 | VOOHU |
| 13 | C I/O · Tuning | USB ESD array | D7 | TVS / ESD | WHTA5V01P2C | VOOHU |
| 14 | D Power stage · Motor | Dual H-bridge gate driver | U5 | — | — | Non-VOOHU |
| 15 | D Power stage · Motor | Dual H-bridge MOSFET ×8 | Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 | — | — | Non-VOOHU |
| 16 | D Power stage · Motor | Phase current sensing (shunt resistors + current amplifier) | U6 R1 R2 | — | — | Non-VOOHU |
| 17 | D Power stage · Motor | DC bus capacitor bank | C1 | — | — | Non-VOOHU |
| 18 | D Power stage · Motor | Motor winding terminal (A+ / A− / B+ / B−) | J5 | — | — | Non-VOOHU |
| 19 | E Core | EtherCAT slave controller (ESC) | U7 | — | — | Non-VOOHU |
| 20 | E Core | Stepper drive MCU | U8 | — | — | Non-VOOHU |
| 21 | E Core | Parameter storage Flash | U9 | — | — | Non-VOOHU |
| 22 | E Core | MCU crystal | Y2 | — | — | Non-VOOHU |
| 23 | E Core | Core supply filter molded inductor ×2 | L4 L5 | Molded Inductors | WHYTA0420 Series | VOOHU |
| 24 | F Power | DC 24 ~ 48V input terminal | J6 | — | — | Non-VOOHU |
| 25 | F Power | Input fuse + TVS | F1 D8 | TVS / ESD | WHTB058VA | VOOHU |
| 26 | F Power | Power line common-mode choke (EMI) | L6 | Power Line CMC | WHAL-1513A-301T0 | VOOHU |
| 27 | F Power | Synchronous buck ×2 (bus→12V→3.3V) | U10 U11 | — | — | Non-VOOHU |
| 28 | F Power | DC-DC molded inductor ×2 | L7 L8 | Molded Inductors | WHYT1030 Series | VOOHU |
Resources & downloads
Board bill of materials
Reference designators, zones, VOOHU categories, recommended parts and availability for all 28 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 stepper drive reference design full package
Includes the BOM, datasheets for the recommended VOOHU parts and position-by-position selection notes. For selection advice tailored to your supply voltage, fieldbus protocol or valve-island node, please include it in your requirements. We reply within 24 hours on working days.
