# SN74LS169BN

**Texas Instruments** · Counters / Dividers · PDIP-16

SN74LS169BN from Texas Instruments, in a PDIP-16. 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 | U/D | input | Up/down input: counts up when high and counts down when low, taking effect on the next clock pulse. |
| 2 | CLK | input | Buffered clock input that triggers all four master-slave flip-flops on the rising (positive-going) edge. |
| 3 | A | input | Data input A, preset into the counter synchronously when LOAD is low. |
| 4 | B | input | Data input B, preset into the counter synchronously when LOAD is low. |
| 5 | C | input | Data input C, preset into the counter synchronously when LOAD is low. |
| 6 | D | input | Data input D, preset into the counter synchronously when LOAD is low. |
| 7 | ENP | input | Active-low count-enable input; both ENP and ENT must be low to count. |
| 8 | GND | power_in | Ground. |
| 9 | LOAD | input | Active-low synchronous load input; a low level disables counting and sets outputs to agree with data inputs after the next clock pulse. |
| 10 | ENT | input | Active-low count-enable input that is also fed forward to enable the carry output; must be low to count. |
| 11 | QD | output | Counter output D, the most significant bit. |
| 12 | QC | output | Counter output C. |
| 13 | QB | output | Counter output B. |
| 14 | QA | output | Counter output A, the least significant bit. |
| 15 | RCO | output | Active-low ripple carry output that pulses low at overflow to enable cascaded stages. |
| 16 | VCC | power_in | Positive supply voltage. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | PDIP-16 |
| Category | Logic ICs |
| Pins | 16 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Operating free-air temperature (orderable range) |  | 0 |  | 70 | °C |  | 12 |

## CAD (KiCad official)

- Symbol: `SN74LS169BN`
- Footprint: `Package_DIP:DIP-16_W7.62mm`
- 3D model: PDIP-16 (KiCad packages3D, STEP)
- 3D model files: `sn74ls169bn-etched.step` / `sn74ls169bn-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `sn74ls169bn.step` / `sn74ls169bn.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/sn74ls169b.pdf) (21 pp, sha256 `64b70ed10dca50ff`, retrieved 2026-10-30, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text+vision), consensus `claude-opus-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/sn74ls169bn-datasheet.pdf)