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Contents

README

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CD74AC161M

Texas Instruments · Counters, Dividers · SOIC-16

CD74AC161M from Texas Instruments, in a SOIC-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 CLR input Asynchronous clear input, active low; sets all Q outputs to low regardless of CLK, LOAD, or enable inputs.
2 CLK input Synchronous clock input, rising edge triggered.
3 A input Data input A for parallel preset operation; loaded to QA when LOAD is low.
4 B input Data input B for parallel preset operation; loaded to QB when LOAD is low.
5 C input Data input C for parallel preset operation; loaded to QC when LOAD is low.
6 D input Data input D for parallel preset operation; loaded to QD when LOAD is low.
7 ENP input Count enable input; ENP and ENT must both be high for counting; does not affect RCO output.
8 GND power_in Ground connection for power return and logic reference.
9 LOAD input Parallel load input, active low; disables counting and loads data A-D to Q outputs on next clock edge.
10 ENT input Count enable input; ENP and ENT must both be high for counting; feed-forward enables RCO at maximum count.
11 QD output Counter output D (most significant bit) for 4-bit binary count.
12 QC output Counter output C for 4-bit binary count.
13 QB output Counter output B for 4-bit binary count.
14 QA output Counter output A (least significant bit) for 4-bit binary count.
15 RCO output Ripple carry output; high pulse when counter reaches maximum (9 or 15) and ENT is high.
16 VCC power_in Power supply input voltage; operating range 1.5V to 5.5V.

Key specifications

Parameter Value
Manufacturer Texas Instruments
Package SOIC-16
Category Logic
Pins 16

CAD (KiCad official)

  • Symbol: CD74AC161M
  • Footprint: Package_SO:SOIC-16_3.9x9.9mm_P1.27mm
  • 3D model: SOIC-16 (KiCad packages3D, STEP)
  • 3D model files: cd74ac161m-etched.step / cd74ac161m-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); cd74ac161m.step / cd74ac161m.glb are the bare package body.

Provenance

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

  • Datasheet: Texas Instruments datasheet (23 pp, sha256 cc0df0be38defb4e, retrieved 2026-09-27, 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: parts-factory 2.0.0 / extract_pins 0.2, primary claude-haiku-4-5-20251001 (text), consensus claude-sonnet-4-6 (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