# SN74CBT3257DBR

**Texas Instruments** · Signal Switches, Multiplexers, Decoders · SSOP-16-208mil

SN74CBT3257DBR from Texas Instruments, in a SSOP-16-208mil. 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 | S | input | TTL-compatible select input for multiplexer path control. |
| 2 | 1B1 | bidirectional | Channel 1 B1 FET switch port. |
| 3 | 1B2 | bidirectional | Channel 1 B2 FET switch port. |
| 4 | 1A | bidirectional | Channel 1 A FET switch port. |
| 5 | 2B1 | bidirectional | Channel 2 B1 FET switch port. |
| 6 | 2B2 | bidirectional | Channel 2 B2 FET switch port. |
| 7 | 2A | bidirectional | Channel 2 A FET switch port. |
| 8 | GND | power_in | Ground, negative supply reference. |
| 9 | 3A | bidirectional | Channel 3 A FET switch port. |
| 10 | 3B2 | bidirectional | Channel 3 B2 FET switch port. |
| 11 | 3B1 | bidirectional | Channel 3 B1 FET switch port. |
| 12 | 4A | bidirectional | Channel 4 A FET switch port. |
| 13 | 4B2 | bidirectional | Channel 4 B2 FET switch port. |
| 14 | 4B1 | bidirectional | Channel 4 B1 FET switch port. |
| 15 | OE | input | TTL-compatible output enable control input, active low. |
| 16 | VCC | power_out | Positive supply voltage, 4 to 5.5 V recommended operating range. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SSOP-16-208mil |
| Category | Logic |
| Pins | 16 |

## CAD (KiCad official)

- Symbol: `SN74CBT3257DBR`
- Footprint: `Package_SO:SSOP-16_5.3x6.2mm_P0.65mm`
- 3D model: SSOP-16-208mil (KiCad packages3D, STEP)
- 3D model files: `sn74cbt3257dbr-etched.step` / `sn74cbt3257dbr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `sn74cbt3257dbr.step` / `sn74cbt3257dbr.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/sn74cbt3257) (16 pp, sha256 `71e61043466ffef3`, retrieved 2026-10-03, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-4-5-20251001` (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/sn74cbt3257dbr-datasheet.pdf)