# Interlink FSR 400 Small Round FSR 5 mm

> Interlink FSR 400 small round force-sensitive resistor (SparkFun SEN-09673): 5.08 mm active area on a 7.62 mm head, 0.1–10 N sensitivity, 0.1 N actuation, ±2 % single-part repeatability, >10 MΩ unloaded, <3 µs rise, −30 to +70 °C, 10 million actuations, 0.35 mm thick, two 0.1 in pins. Fingertip-sized: the go-to for robot fingertips and small buttons.

- Manufacturer: Interlink Electronics
- Part number: 30-49649
- Category: Tactile & touch sensors
- Canonical page: https://www.xirkit.io/products/interlink-fsr-400-small-round-fsr-5-mm-9120
- Pinout: https://www.xirkit.io/products/interlink-fsr-400-small-round-fsr-5-mm-9120/pinout
- Structured JSON: https://www.xirkit.io/products/interlink-fsr-400-small-round-fsr-5-mm-9120/data.json
- Source: Xirkit structured parts catalog — every value traced to a cited document; unknowns are explicit.

## Key specifications

| Property | Value |
| --- | --- |
| Sensing | force sensitive resistor |
| Active area shape | round |
| Active area diameter | 5.08 mm |
| Force range (min) | 0.1 N |
| Force range (max) | 10 N |
| Output | analog: resistance falls with force (>10 MΩ unloaded) |
| Interface | analog |
| Thickness | 0.35 mm |
| Dimensions | 38.1 × 7.62 × 0.35 mm |
| Operating temperature | -30 to 70 °C |

## Pinout (2 pins, 0 with electrical limits)

| Pin | Position | Kind | Chip pad | Functions | VIH | VIL | VOH | VOL | IOH | IOL | 5 V tolerant |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| T1 | — | terminal | — | t1 | — | — | — | — | — | — | — |
| T2 | — | terminal | — | t2 | — | — | — | — | — | — | — |

## Where to buy

| Supplier | Price | Stock | Checked | URL |
| --- | --- | --- | --- | --- |
| SparkFun | 10.95 USD | unknown | 2026-10-01 | https://www.sparkfun.com/products/9673 |

## FAQ

**How much does the Interlink FSR 400 Small Round FSR 5 mm cost?**

From $10.95 at SparkFun. Prices are observed unit prices before tax and shipping.

**What are the Interlink FSR 400 Small Round FSR 5 mm dimensions?**

38.1 × 7.62 × 0.35 mm. A STEP model is available for enclosure fit checks.

**Where does this Interlink FSR 400 Small Round FSR 5 mm 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

- [Interlink FSR 400 Small Round FSR 5 mm datasheet](https://cdn.sparkfun.com/datasheets/Sensors/ForceFlex/2010-10-26-DataSheet-FSR400-Layout2.pdf)
- [SparkFun listing](https://www.sparkfun.com/products/9673)

## Part graph

### Alternatives (by use case)

- [Alpha MF02A Square FSR 38 mm (1–49 N)](https://www.xirkit.io/products/alpha-mf02a-square-fsr-38-mm-1-49-n-09b0) — Both serve grasping and manipulation — check the trade-offs; $10.95 vs $5.95
- [Interlink FSR 402 Round FSR 12.7 mm](https://www.xirkit.io/products/interlink-fsr-402-round-fsr-12-7-mm-3272) — Both serve grasping and manipulation — check the trade-offs; $10.95 vs $10.95
- [Interlink FSR 406 Square FSR 38 mm](https://www.xirkit.io/products/interlink-fsr-406-square-fsr-38-mm-388a) — Both serve grasping and manipulation — check the trade-offs; $10.95 vs $17.5
- [Adafruit MPR121 12-Key Capacitive Touch](https://www.xirkit.io/products/adafruit-mpr121-12-key-capacitive-touch-b241) — Both serve touch and force sensing — check the trade-offs; $10.95 vs $7.95
- [Adafruit AT42QT1010 Capacitive Touch (momentary)](https://www.xirkit.io/products/adafruit-at42qt1010-capacitive-touch-momentary-ba53) — Both serve touch and force sensing — check the trade-offs; $10.95 vs $5.95
- [Interlink FSR 408 Long Strip, 24 in](https://www.xirkit.io/products/interlink-fsr-408-long-strip-24-in-d29d) — Both serve grasping and manipulation — check the trade-offs; $10.95 vs $19.95
- [Adafruit AT42QT1070 5-Pad Touch Sensor](https://www.xirkit.io/products/adafruit-at42qt1070-5-pad-touch-sensor-a70d) — Both serve touch and force sensing — check the trade-offs; $7.5 vs $10.95
- [Seeed Grove Round Force Sensor (FSR402)](https://www.xirkit.io/products/seeed-grove-round-force-sensor-fsr402-ede8) — Both serve grasping and manipulation — check the trade-offs; $14.9 vs $10.95
- [Adafruit AT42QT1012 Capacitive Touch (toggle)](https://www.xirkit.io/products/adafruit-at42qt1012-capacitive-touch-toggle-8b03) — Both serve touch and force sensing — check the trade-offs; $5.95 vs $10.95
- [Adafruit MPR121 Gator Capacitive Touch](https://www.xirkit.io/products/adafruit-mpr121-gator-capacitive-touch-52df) — Both serve touch and force sensing — check the trade-offs; $6.95 vs $10.95