# LP311DR

**Texas Instruments** · Comparators · SOIC-8

LP311DR from Texas Instruments, in a SOIC-8. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | EMIT OUT | output | Emitter output, which can swing below the negative supply; voltage from emitter output to VCC− is rated at 30 V maximum. |
| 2 | IN+ | input | Non-inverting comparator input; with |VCC±| ≤ 15 V the input voltage must stay between VCC− + 0.5 V and VCC+ − 1.5 V, and the input voltage magnitude must never exceed ±15 V. |
| 3 | IN− | input | Inverting comparator input; with |VCC±| ≤ 15 V the input voltage must stay between VCC− + 0.5 V and VCC+ − 1.5 V, and the input voltage magnitude must never exceed ±15 V. |
| 4 | VCC− | power_in | Negative supply rail; the supply voltage VCC+ − VCC− is specified from 3.5 V to 30 V. |
| 5 | BALANCE | passive | Offset-balancing pin used with a trim network to minimize input offset voltage; if offset balancing is not used, it should be shorted to BAL/STRB. |
| 6 | BAL/STRB | input | Strobe input that turns the output off regardless of the inputs when pulled low; it must be current driven at 100 µA to 300 µA and must not be connected directly to ground. |
| 7 | COL OUT | output | Collector output with 25 mA drive capability; voltage from collector output to VCC− is rated at 40 V maximum. |
| 8 | VCC+ | power_in | Positive supply rail; the supply voltage VCC+ − VCC− is specified from 3.5 V to 30 V. |

## Key specifications

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

## CAD (KiCad official)

- Symbol: `LP311DR`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files: `lp311dr-etched.step` / `lp311dr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lp311dr.step` / `lp311dr.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/lit/ds/symlink/lp311.pdf) (14 pp, sha256 `3c7d5a253861da53`, retrieved 2026-10-08, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/lp311dr-datasheet.pdf)