# SOYO NEMA 23 Stepper 57×56 mm 2.8 A

> SOYO SY57STH56-2804A NEMA 23 hybrid bipolar stepper: 1.8° step (200 steps/rev), 2.8 A per coil at 2.52 V, 0.9 Ω / 2.5 mH per phase, 126 N·cm (13 kg·cm) holding torque, 56.4 mm square × 56 mm body, 6.35 mm D-shaft, 0.7 kg, four 30 cm bare leads.

- Manufacturer: SOYO
- Part number: SY57STH56-2804A
- Category: Motors
- Canonical page: https://www.xirkit.io/products/soyo-nema-23-stepper-57-56-mm-2-8-a-e418
- Pinout: https://www.xirkit.io/products/soyo-nema-23-stepper-57-56-mm-2-8-a-e418/pinout
- Structured JSON: https://www.xirkit.io/products/soyo-nema-23-stepper-57-56-mm-2-8-a-e418/data.json
- Source: Xirkit structured parts catalog — every value traced to a cited document; unknowns are explicit.

## Key specifications

| Property | Value |
| --- | --- |
| Motor type | stepper |
| Rated voltage | 2.52 V |
| Holding torque | 1.26 N·m |
| Rated current | 2.8 A |
| Step angle | 1.8° |
| Shaft diameter | 6.35 mm |
| Dimensions | 56.4 × 56.4 × 77 mm |
| Operating temperature | -20 to 50 °C |
| Certifications | RoHS 3 |

## Pinout (4 pins, 0 with electrical limits)

| Pin | Position | Kind | Chip pad | Functions | VIH | VIL | VOH | VOL | IOH | IOL | 5 V tolerant |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| BLK | — | phase a plus | — | blk | — | — | — | — | — | — | — |
| GRN | — | phase a minus | — | grn | — | — | — | — | — | — | — |
| RED | — | phase b plus | — | red | — | — | — | — | — | — | — |
| BLU | — | phase b minus | — | blu | — | — | — | — | — | — | — |

## Where to buy

| Supplier | Price | Stock | Checked | URL |
| --- | --- | --- | --- | --- |
| www.pololu.com | 76.72 USD | in_stock | 2026-09-28 | https://www.pololu.com/product/1474 |

## FAQ

**How much does the SOYO NEMA 23 Stepper 57×56 mm 2.8 A cost?**

From $76.72 at www.pololu.com. Prices are observed unit prices before tax and shipping.

**What are the SOYO NEMA 23 Stepper 57×56 mm 2.8 A dimensions?**

56.4 × 56.4 × 77 mm. A STEP model is available for enclosure fit checks.

**Where does this SOYO NEMA 23 Stepper 57×56 mm 2.8 A data come from?**

Every value in this record is traced to a source — 2 documents including the board and chip datasheets — with the page and table cited per value. Unknowns are left explicit, never guessed.

## Sources

- [SOYO NEMA 23 Stepper 57×56 mm 2.8 A datasheet](https://www.pololu.com/file/0J674/SY57STH56-2804A.pdf)
- [www.pololu.com listing](https://www.pololu.com/product/1474)

## Part graph

### Variants

- [SOYO NEMA 23 Stepper 57×76 mm 2.8 A](https://www.xirkit.io/products/soyo-nema-23-stepper-57-76-mm-2-8-a-f77d) — Same SOYO SY57STH series, same NEMA 23 flange (56.4 mm, 4-Ø5 on 47.1 mm, Ø38.1 pilot, Ø6.35 D-shaft) and 2.8 A phase current; 76 mm stack gives 189 vs 126 N·cm holding torque (drawings p1)