# Feetech STS3215-C001 19.5 kg·cm Servo

> Feetech STS3215-C001 is the 7.4 V serial bus servo used in the LeRobot SO-ARM101 arm: 19.5 kg·cm stall and 5 kg·cm rated torque at 7.4 V, 52 rpm no-load, 1:345 copper gear train, 12-bit magnetic encoder (4096 steps, 0.088°), TTL bus up to 1 Mbps with IDs 0–253, 4–7.4 V, 55 g, 45.2 × 24.7 × 35 mm. Do not run it on 12 V: over-voltage protection trips above 8 V.

- Manufacturer: Feetech
- Part number: STS3215-C001
- Category: Actuators
- Canonical page: https://www.xirkit.io/products/feetech-sts3215-c001-19-5-kg-cm-servo-796d
- Pinout: https://www.xirkit.io/products/feetech-sts3215-c001-19-5-kg-cm-servo-796d/pinout
- Structured JSON: https://www.xirkit.io/products/feetech-sts3215-c001-19-5-kg-cm-servo-796d/data.json
- Source: Xirkit structured parts catalog — every value traced to a cited document; unknowns are explicit.

## Key specifications

| Property | Value |
| --- | --- |
| Actuator type | smart_servo |
| Gearbox | 345:1 |
| Rated torque | 0.49 N·m |
| Peak torque | 1.912 N·m |
| No-load speed | 52 rpm |
| Rated voltage | 7.4 V |
| Rated current | 0.65 A |
| Torque constant Kt | 0.765 N·m/A |
| Backlash | 0.5° |
| Encoder | 12-bit magnetic, 360° (4096 per turn, 0.088°) |
| Control interface | TTL |
| Control modes | position (servo mode), closed-loop speed, open-loop speed, step, multi-turn position |
| Dimensions | 45.2 × 24.7 × 35 mm |
| Operating temperature | -20 to 60 °C |
| Certifications | RoHS, EMC |

## Pinout (3 pins, 0 with electrical limits)

| Pin | Position | Kind | Chip pad | Functions | VIH | VIL | VOH | VOL | IOH | IOL | 5 V tolerant |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| GND | 5264-3P · 1 | ground | — | ground | — | — | — | — | — | — | — |
| Vcc | 5264-3P · 2 | power in | — | power_in | — | — | — | — | — | — | — |
| Signal/TTL | 5264-3P · 3 | signal | — | signal/ttl | — | — | — | — | — | — | — |

## Where to buy

| Supplier | Price | Stock | Checked | URL |
| --- | --- | --- | --- | --- |
| www.seeedstudio.com | 20 USD | in_stock | 2026-10-06 | https://www.seeedstudio.com/STS3215-19kg-cm-7-4V-Serial-Servo-p-6338.html |
| aifitlab.com | 23 USD | in_stock | 2026-10-06 | https://aifitlab.com/products/feetech-sts3215-servo-motor?variant=43455639552136 |

## FAQ

**What voltage powers the Feetech STS3215-C001 19.5 kg·cm Servo?**

Supply range 4–7.4 V.

**How much does the Feetech STS3215-C001 19.5 kg·cm Servo cost?**

From $20 at www.seeedstudio.com (2 supplier offers tracked). Prices are observed unit prices before tax and shipping.

**What are the Feetech STS3215-C001 19.5 kg·cm Servo dimensions?**

45.2 × 24.7 × 35 mm. A STEP model is available for enclosure fit checks.

**Where does this Feetech STS3215-C001 19.5 kg·cm Servo data come from?**

Every value in this record is traced to a source — 3 documents including the board and chip datasheets — with the page and table cited per value. Unknowns are left explicit, never guessed.

## Sources

- [Feetech STS3215-C001 19.5 kg·cm Servo datasheet](https://files.seeedstudio.com/products/Feetech/108090023_STS3215-C001_Datasheet.pdf)
- [www.seeedstudio.com listing](https://www.seeedstudio.com/STS3215-19kg-cm-7-4V-Serial-Servo-p-6338.html)
- [aifitlab.com listing](https://aifitlab.com/products/feetech-sts3215-servo-motor?variant=43455639552136)

## Part graph

### Alternatives (by use case)

- [ROBOTIS DYNAMIXEL XL330-M077-T](https://www.xirkit.io/products/robotis-dynamixel-xl330-m077-t-1a93) — Both serve robot joints and actuation — check the trade-offs; $20 vs $27.49
- [Waveshare ST3215 Servo 30 kg·cm 12 V](https://www.xirkit.io/products/waveshare-st3215-servo-30-kg-cm-12-v-250d) — Both serve robot joints and actuation — check the trade-offs; $20 vs $21.99
- [Waveshare ST3020 Servo 25 kg·cm 12 V](https://www.xirkit.io/products/waveshare-st3020-servo-25-kg-cm-12-v-3bb1) — Both serve robot joints and actuation — check the trade-offs; $20 vs $19.99
- [M5Stack Roller485 BLDC Unit (U182)](https://www.xirkit.io/products/m5stack-roller485-bldc-unit-u182-5e1c) — Both serve robot joints and actuation — check the trade-offs; $20 vs $36.95
- [goBILDA Dual Mode Servo 25-4 Super Speed](https://www.xirkit.io/products/gobilda-dual-mode-servo-25-4-super-speed-68d7) — Both serve robot joints and actuation — check the trade-offs; $20 vs $36.99
- [Waveshare SC15 Servo 15 kg·cm 6 V](https://www.xirkit.io/products/waveshare-sc15-servo-15-kg-cm-6-v-a32f) — Both serve robot joints and actuation — check the trade-offs; $20 vs $17.99
- [Waveshare ST3215-HS Servo 20 kg·cm 12 V](https://www.xirkit.io/products/waveshare-st3215-hs-servo-20-kg-cm-12-v-c2c5) — Both serve robot joints and actuation — check the trade-offs; $20 vs $21.99
- [ROBOTIS DYNAMIXEL XL330-M288-T](https://www.xirkit.io/products/robotis-dynamixel-xl330-m288-t-db1e) — Both serve robot joints and actuation — check the trade-offs; $20 vs $27.49

### Variants

- [Feetech STS3215-C046 14.4 kg·cm Servo](https://www.xirkit.io/products/feetech-sts3215-c046-14-4-kg-cm-servo-3afb) — Same STS3215 body (45.2 × 24.7 × 35 mm), connector and TTL protocol; C046 is geared 1:147 (106 rpm, 14.4 kg·cm stall at 7.4 V) vs 1:345 on the C001 (52 rpm, 19.5 kg·cm)
- [Feetech STS3215-C018 30 kg·cm 12V Servo](https://www.xirkit.io/products/feetech-sts3215-c018-30-kg-cm-12v-servo-8711) — Same STS3215 body, 1:345 gearing and TTL protocol; C018 is the 12 V version (30 kg·cm stall, 4–14 V) — the 7.4 V C001 trips over-voltage above 8 V, so do not mix them on one supply
- [Feetech STS3215-C044 27.4 kg·cm Servo](https://www.xirkit.io/products/feetech-sts3215-c044-27-4-kg-cm-servo-911c) — Same STS3215 body (45.2 × 24.7 × 35 mm), connector and TTL protocol; C044 is geared 1:191 (86 rpm, 27.4 kg·cm stall at 7.4 V) vs 1:345 on the C001 (52 rpm, 19.5 kg·cm)