This document describes multiple models of octal bus transceivers and registers, including SN54ALS652, SN54ALS653, SN54AS651, SN54AS652, SN74ALS651A, SN74ALS652A, SN74ALS653, SN74ALS654, SN74AS651, and SN74AS652. These devices have independent registers and enables for A and B buses, allowing multiplexed transmission of real-time and stored data. Users can choose between true or inverting data paths, as well as 3-state or open-collector outputs to the A bus. The document also mentions different package options.
The document provides detailed information on Texas Instruments octal bus transceivers and registers with 3‑state outputs, including part numbers SN54ALS652, SN54ALS653, SN54AS651, SN54AS652, SN74ALS651A, SN74ALS652A, SN74ALS653, SN74ALS654, SN74AS651 and SN74AS652. It describes the functional operation, package options, and pin configurations for each device.
Key sections cover absolute maximum ratings, recommended operating conditions, electrical characteristics, timing diagrams, and a notice on product availability and warranty. The data sheet also includes tables of logic symbols, function tables, and parameter measurement information.
| High‑level input voltage (VIH) | 2 V |
|---|---|
| Low‑level input voltage (VIL) | 0.7 V – 0.8 V |
| High‑level output current (IOH) | -12 mA (SN54ALS) / -15 mA (SN74ALS) |
| Clock frequency | 0 – 35 MHz (SN54ALS) / 0 – 40 MHz (SN74ALS) |
The SN74ALS series can source up to –15 mA on a high‑level output.