# XTR115U

**Texas Instruments** · Special Purpose Amplifiers · SOIC-8

XTR115U from Texas Instruments, in a SOIC-8. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | VREF | output | Precision voltage reference output. 2.5V on XTR115 (4.096V on XTR116). Used to excite sensors or provide offsets. |
| 2 | IIN | input | Current input pin to the internal control amplifier (A1). The loop output current is IO = 100 x IIN. |
| 3 | IRET | input | Local ground return pin for VREG and VREF currents. Used to sense and include the regulator/reference return current in the loop output for high accuracy. |
| 4 | IO | output | Regulated 4mA to 20mA current-loop output. Connects to the external pass transistor emitter path returning to the loop negative side. |
| 5 | E | input | External NPN pass transistor emitter connection. Provides the sense/feedback point for the loop current control loop. |
| 6 | B | output | External NPN pass transistor base drive output. Driven by the internal error amplifier to regulate loop current. |
| 7 | V+ | power_in | Loop power supply input. Operating range 7.5V to 36V (absolute max 40V). |
| 8 | VREG | power_out | 5V regulator voltage output, available to power external sensor/signal-conditioning circuitry from the loop supply. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOIC-8 |
| Category | Amplifiers/Comparators |
| Pins | 8 |

## Ordering variants

Same part, different packaging or reel option.

- `XTR115UU`

## CAD (KiCad official)

- Symbol: `XTR115U`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files: `xtr115u-etched.step` / `xtr115u-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `xtr115u.step` / `xtr115u.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/cn/lit/gpn/xtr115) (25 pp, sha256 `fb298d4a78fc8212`, retrieved 2026-08-17, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **Extractor:** `ds2sf` (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/xtr115u-datasheet.pdf)