Texas Instruments SN74ABT652ADBRE4

Overview

SN74ABT652ADBRE4 from Texas Instruments is an octal registered transceiver with 3-state outputs, designed for bidirectional data bus management between two 8-bit buses (A and B). It integrates D-type flip-flops, dual clock inputs (CLKAB/CLKBA), select controls (SAB/SBA), and independent output enables (OEAB/OEBA), supporting real-time or stored-data transfer at up to 125 MHz. It operates from 4.5 V to 5.5 V and is rated for –40°C to 85°C industrial temperature range.

For engineers reviewing the SN74ABT652ADBRE4 datasheet, SN74ABT652ADBRE4 pinout, SN74ABT652ADBRE4 application, or SN74ABT652ADBRE4 equivalent, key selection considerations include its dual-register architecture, high-drive capability (–32 mA IOH / 64 mA IOL), glitch-free select control, and SSOP-24 package compatibility with space-constrained board layouts.

Technical Context

The SN74ABT652ADBRE4 implements a dual-path bus transceiver with independent A→B and B→A data paths, each controlled by dedicated clock, select, and enable signals. Its EPIC-II^B BiCMOS process enables low power dissipation while delivering high-output drive strength and robust ESD protection (>2000 V HBM).

It supports four fundamental bus-management functions: real-time bidirectional transfer, isolated storage of A/B bus data, simultaneous storage in both registers, and cross-bus transfer of stored data - all without decoding glitches during mode transitions due to its synchronous select-control logic.

Key Specifications

Pinout & Package

SN74ABT652ADBRE4 is housed in a 24-pin Shrink Small-Outline Package (SSOP-DB), with 0.64-mm lead pitch and exposed pad not present. Pin 1 is located at top-left corner (Q1 quadrant per tape specification), and the package complies with JEDEC MO-150.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal registered transceiver applications.

Compared with SN74ABT652ADW, the SN74ABT652ADBRE4 offers identical logic and timing but in a 30% smaller SSOP footprint with tighter lead pitch - critical for high-density routing. Versus SN74ABT245DBR, it adds full dual-register control at the cost of 1.5 ns added delay, enabling time-critical synchronous bus bridging impossible with nonregistered alternatives.

Availability

SN74ABT652ADBRE4 is available at Aetrix Electronics and suitable for industrial PLC backplanes, memory expansion buffers, test equipment data acquisition hubs, and legacy bus protocol translators requiring stable component supply across long production lifecycles.

Supply support for SN74ABT652ADBRE4 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions, with decades of heritage in industry-standard logic families.

The SN74ABT652ADBRE4 belongs to TI's ABT logic series - engineered for high-speed, low-power 5-V bus interface applications in industrial automation, instrumentation, and communications infrastructure.

FAQ

What is the function of the SAB and SBA pins on the SN74ABT652ADBRE4?

The SAB and SBA pins on the SN74ABT652ADBRE4 are select-control inputs that determine whether real-time or stored data is transferred in their respective directions. A low level on SAB selects real-time A-bus data for transfer to the B-bus; a high level selects data previously latched into the A-side register. Similarly, SBA controls B→A transfer mode. This architecture eliminates multiplexer glitches during mode transitions.

Does the SN74ABT652ADBRE4 support hot insertion or live bus swapping?

The SN74ABT652ADBRE4 does not include explicit hot-swap circuitry such as current limiting or soft-start. However, its high-impedance 3-state outputs, robust ESD protection (>2000 V HBM), and power-up default isolation (when OEBA is pulled to VCC and OEAB to GND) allow safe insertion into powered-backplane systems - provided external current-limiting resistors and sequencing controls are implemented per TI application guidelines.

What is the maximum capacitive load the SN74ABT652ADBRE4 can drive reliably?

The SN74ABT652ADBRE4 is characterized with CL = 50 pF in its switching specifications, and its 64-mA low-level output drive supports stable operation into ≥80 pF loads at 100 MHz with <1-V ground bounce (VOLP < 1 V). For sustained 125-MHz operation, TI recommends limiting total trace + load capacitance to ≤60 pF using controlled-impedance routing and local termination.

Can the SN74ABT652ADBRE4 operate at 3.3 V?

No, the SN74ABT652ADBRE4 is specified only for 4.5 V to 5.5 V supply operation. Its ABT-family input thresholds, output drive strength, and internal BiCMOS biasing are optimized for 5-V TTL-compatible systems. Operating below 4.5 V risks undefined logic states, reduced noise margin, and failure to meet timing specifications - use SN74LVC245A or similar 3.3-V logic for lower-voltage applications.

How should unused pins be handled on the SN74ABT652ADBRE4?

Per TI's recommended operating conditions, all unused input or I/O pins on the SN74ABT652ADBRE4 must be held at a valid logic level - either tied to VCC or GND - to prevent floating states that cause increased ICC, noise coupling, or potential latch-up. NC (no-connect) pins - specifically pins 14 and 15 - must remain unconnected and un-routed.