Texas Instruments SN74ABT623DBLE

Overview

SN74ABT623DBLE from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data communication between A and B buses in industrial and computing systems. It features dual output-enable inputs (OEAB/OEBA), high-drive capability (–32 mA IOH, 64 mA IOL), operates at 4.5–5.5 V, and is rated for –40°C to 85°C.

For engineers reviewing the SN74ABT623DBLE datasheet, SN74ABT623DBLE pinout, SN74ABT623DBLE application, or SN74ABT623DBLE equivalent, key selection considerations include its dual-enable control logic, bus-isolation behavior during power sequencing, ground-bounce performance (<1 V VOLP), and compatibility with 5-V TTL/CMOS system interfaces.

Technical Context

This device implements true bidirectional data flow using two independent 3-state enable controls: OEAB enables A→B transmission, OEBA enables B→A transmission. Simultaneous assertion of both enables allows bus latching-each port reinforces its own data while isolating external drivers.

It uses EPIC-II^B BiCMOS technology to achieve low power dissipation and high noise immunity. Input thresholds meet standard TTL levels (VIH = 2 V, VIL = 0.8 V), and output drive strength supports heavy capacitive loads typical in backplane and motherboard interconnects.

Key Specifications

Pinout & Package

SN74ABT623DBLE is housed in a 20-pin Shrink Small-Outline Package (SSOP, DB), 7.5 mm × 5.6 mm body, 0.65 mm pitch, 1.95 mm height. Pin 1 marked via notch or bevel; gull-wing leads for surface-mount assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ABT245DBR and 74LVC245APW, SN74ABT623DBLE uniquely supports true bidirectional latching without external flip-flops, delivers higher drive into 5-V loads, and maintains industrial temperature range-making it optimal for legacy 5-V bus isolation where timing-critical bus ownership handoff is required.

Availability

SN74ABT623DBLE is available at Aetrix Electronics and suitable for industrial automation, legacy computing infrastructure, and automated test equipment requiring stable component supply and long-term obsolescence management.

Supply support for SN74ABT623DBLE 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 high-reliability interface ICs.

SN74ABT623DBLE belongs to the ABT logic family-designed specifically for high-speed, high-drive 5-V bus interfacing in industrial and computing systems where signal integrity and bus contention control are critical.

FAQ

What is the recommended power-up sequencing for SN74ABT623DBLE to avoid bus contention?

During power-up, OEBA must be held high (tied to VCC via pullup resistor) and OEAB held low (tied to GND via pulldown resistor) to ensure both A and B ports enter high-impedance state before valid logic levels are established. The minimum pullup/pulldown values depend on driver current-sourcing/sinking capability per TI SCBS114D guidelines. This prevents unintended data coupling before system initialization completes.

Does SN74ABT623DBLE support hot-swap operation?

SN74ABT623DBLE is not hot-swap rated per IEC 61000-4-2 or JEDEC JESD63. While its ESD protection (>2000 V HBM) provides board-level handling robustness, the device lacks controlled slew-rate outputs or power-on reset circuitry needed for live insertion. For hot-swap applications, external protection circuitry and sequencing controllers are required alongside SN74ABT623DBLE.

Can SN74ABT623DBLE operate reliably at 4.5 V supply?

Yes. SN74ABT623DBLE is fully specified down to 4.5 V per its recommended operating conditions. At VCC = 4.5 V, it maintains VOH ≥ 2.0 V (IOH = –32 mA), VOL ≤ 0.55 V (IOL = 64 mA), and propagation delays within datasheet limits-ensuring interoperability with TTL and CMOS inputs across the full industrial temperature range.

How does the dual-enable latching function work in SN74ABT623DBLE?

When both OEAB and OEBA are low, SN74ABT623DBLE enters latched mode: each port's outputs reinforce their own inputs, holding last valid states on both A and B buses. This occurs only if all other drivers on both buses are in high-impedance state. The latching is dynamic-not storage-based-and collapses immediately upon either OE going high.

Is SN74ABT623DBLE pin-compatible with SN74ABT623DBR?

Yes. SN74ABT623DBLE and SN74ABT623DBR share identical DB-package footprint, pinout, and electrical specifications. The "LE" suffix denotes tape-and-reel packaging for legacy procurement; "BR" indicates current green/RoHS-compliant tape-and-reel. Both are mechanically and electrically interchangeable in PCB layout.