# SN74LV540APW

**Texas Instruments** · Buffers, Drivers, Receivers, Transceivers · TSSOP-20

SN74LV540APW from Texas Instruments, in a TSSOP-20. 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 | OE1 | input | Active-low output enable 1; a high level on OE1 or OE2 forces all eight outputs into the high-impedance state. |
| 2 | A1 | input | Data input A1; inputs accept voltages up to 5.5 V at any valid VCC, and enabled outputs provide inverted data. |
| 3 | A2 | input | Data input A2; inputs accept voltages up to 5.5 V at any valid VCC, and enabled outputs provide inverted data. |
| 4 | A3 | input | Data input A3; inputs accept voltages up to 5.5 V at any valid VCC, and enabled outputs provide inverted data. |
| 5 | A4 | input | Data input A4; inputs accept voltages up to 5.5 V at any valid VCC, and enabled outputs provide inverted data. |
| 6 | A5 | input | Data input A5; inputs accept voltages up to 5.5 V at any valid VCC, and enabled outputs provide inverted data. |
| 7 | A6 | input | Data input A6; inputs accept voltages up to 5.5 V at any valid VCC, and enabled outputs provide inverted data. |
| 8 | A7 | input | Data input A7; inputs accept voltages up to 5.5 V at any valid VCC, and enabled outputs provide inverted data. |
| 9 | A8 | input | Data input A8; inputs accept voltages up to 5.5 V at any valid VCC, and enabled outputs provide inverted data. |
| 10 | GND | power_in | Ground pin. |
| 11 | Y8 | output | Data output Y8 provides inverted data when enabled and must not sink or source more than 35 mA per output (70 mA total for the part). |
| 12 | Y7 | output | Data output Y7 provides inverted data when enabled and must not sink or source more than 35 mA per output (70 mA total for the part). |
| 13 | Y6 | output | Data output Y6 provides inverted data when enabled and must not sink or source more than 35 mA per output (70 mA total for the part). |
| 14 | Y5 | output | Data output Y5 provides inverted data when enabled and must not sink or source more than 35 mA per output (70 mA total for the part). |
| 15 | Y4 | output | Data output Y4 provides inverted data when enabled and must not sink or source more than 35 mA per output (70 mA total for the part). |
| 16 | Y3 | output | Data output Y3 provides inverted data when enabled and must not sink or source more than 35 mA per output (70 mA total for the part). |
| 17 | Y2 | output | Data output Y2 provides inverted data when enabled and must not sink or source more than 35 mA per output (70 mA total for the part). |
| 18 | Y1 | output | Data output Y1 provides inverted data when enabled and must not sink or source more than 35 mA per output (70 mA total for the part). |
| 19 | OE2 | input | Active-low output enable 2; a high level on OE2 or OE1 forces all eight outputs into the high-impedance state. |
| 20 | VCC | power_in | Power supply pin; VCC operates from 2 V to 5.5 V, and a 0.1 µF bypass capacitor is recommended close to the pin for a single supply. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | TSSOP-20 |
| Category | Logic |
| Pins | 20 |

## CAD (KiCad official)

- Symbol: `SN74LV540APW`
- Footprint: `Package_SO:TSSOP-20_4.4x6.5mm_P0.65mm`
- 3D model: TSSOP-20 (KiCad packages3D, STEP)
- 3D model files: `sn74lv540apw-etched.step` / `sn74lv540apw-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `sn74lv540apw.step` / `sn74lv540apw.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/sn74lv540a.pdf) (29 pp, sha256 `c5ca547bc295e586`, retrieved 2026-10-11, 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/sn74lv540apw-datasheet.pdf)