NXP Semiconductors 74ABT651D,112

Overview

74ABT651D,112 from NXP Semiconductors (formerly Philips) is an octal inverting transceiver/register with 3-State outputs, dual clock and select controls, and independent A/B bus registers. It supports real-time bidirectional data transfer and stored-data multiplexing at up to 300 MHz clock frequency, with ±64 mA/–32 mA output drive, and operates across –40 °C to +85 °C. It is used in high-speed bus interface applications such as memory expansion and microprocessor system backplanes.

For engineers reviewing the 74ABT651D,112 datasheet, 74ABT651D,112 pinout, 74ABT651D,112 application, or 74ABT651D,112 equivalent, key selection considerations include its inverting logic behavior, simultaneous A/B register storage capability, live insertion support, power-up 3-State reset, and compatibility with 5 V TTL-level systems requiring high-output-drive bus buffering.

Technical Context

The 74ABT651D,112 implements a BiCMOS architecture enabling low static current (110 µA quiescent) alongside high-speed propagation (3.8 ns typical CPAB→Bn), while maintaining robust latch-up immunity (>500 mA) and ESD protection (>2000 V HBM). Its dual-clock (CPAB/CPBA) and dual-select (SAB/SBA) structure enables four distinct operating modes: real-time A↔B transfer, isolated storage of A or B data, concurrent A+B storage, and selective output of stored data to either bus.

Control logic is fully synchronous: data loads on LOW-to-HIGH clock transitions, and output enable (OEAB/OEBA) is active-LOW with independent direction control. The device features power-up 3-State and low-voltage reset behavior (VRST3 ≤ 0.55 V), ensuring deterministic initialization without external reset circuitry in 5 V systems.

Key Specifications

Pinout & Package

74ABT651D,112 is housed in a 24-pin plastic SO (Small Outline) package per SOT137-1, 7.5 mm body width, surface-mount compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal inverting transceiver/register applications.

Compared with 74ABT651D,112, the 74ABT652D,112 offers identical performance and footprint without inversion - ideal for polarity-sensitive interfaces - while the SN74ABT16245DGGR trades register depth and dual-bus control for doubled width and simpler control, making it suitable only for basic unidirectional or bidirectional bus extension without data staging.

Availability

74ABT651D,112 is available at Aetrix Electronics and suitable for industrial automation, telecommunications infrastructure, and embedded computing applications requiring stable component supply, long-lifecycle support, and guaranteed traceability for safety-critical designs.

Supply support for 74ABT651D,112 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

NXP Semiconductors, formerly Philips Semiconductors, is a global leader in high-performance logic, automotive, and secure connectivity ICs, with deep heritage in industrial-grade interface solutions.

The 74ABT651D,112 belongs to the ABT (Advanced BiCMOS Technology) logic family, designed specifically for high-speed, low-power 5 V bus interface applications demanding robust noise immunity and hot-swap capability in harsh environments.

FAQ

What is the logic polarity of the 74ABT651D,112?

The 74ABT651D,112 is an inverting octal transceiver/register: data appearing at A0–A7 or B0–B7 outputs is logically inverted relative to the corresponding input. This behavior applies to both real-time pass-through and registered output modes, and is intrinsic to the device's architecture - no external inversion is needed or implied.

Does the 74ABT651D,112 support simultaneous clocking of both A and B registers?

Yes - the 74ABT651D,112 permits simultaneous LOW-to-HIGH transitions on CPAB and CPBA only when both SAB and SBA are LOW. If either select input is HIGH, clocks must be staggered to avoid undefined register behavior, as specified in the Function Table footnote ** on page 4 of the datasheet.

What is the maximum capacitive load the 74ABT651D,112 can drive reliably?

The 74ABT651D,112 is characterized for CL = 50 pF in AC specifications, and its ±64 mA/–32 mA output drive supports sustained operation into ≥50 pF loads at full speed. For heavier loads (>75 pF), propagation delay increases linearly and maximum frequency decreases - design validation at target load is recommended.

How does the 74ABT651D,112 behave during power-up?

At power-up, the 74ABT651D,112 enters a defined 3-State condition: all outputs go high-impedance, and internal registers initialize to a known state. VRST3 is guaranteed ≤ 0.55 V, ensuring outputs remain safely LOW during ramp-up - no external reset or pull-up is required for deterministic startup.

Is the 74ABT651D,112 pin-compatible with the 74ABT651N or 74ABT651PW variants?

Yes - the 74ABT651D,112 (SO24), 74ABT651N (DIP24), and 74ABT651PW (TSSOP24) share identical pin numbering, signal assignment, and electrical functionality. Only package dimensions and mounting method differ; PCB layout must match the selected package's footprint and thermal pad requirements.