Texas Instruments 74ACT11652DW

Overview

74ACT11652DW from Texas Instruments is an octal bus transceiver and register IC with independent A/B bus control, 3-state outputs, real-time/stored data multiplexing, and flow-through architecture optimized for PCB layout. It operates from –40°C to 85°C at 4.5–5.5 V, supports 105 MHz clock frequency, and features EPIC 1-µm CMOS process with 500-mA latch-up immunity.

For engineers reviewing the 74ACT11652DW datasheet, 74ACT11652DW pinout, 74ACT11652DW application, or 74ACT11652DW equivalent, key selection criteria include simultaneous real-time and stored data routing capability, independent enable/select control per bus, center-pin VCC/GND noise reduction, and guaranteed 24-mA drive strength across temperature.

Technical Context

This device integrates eight D-type flip-flops, dual-directional transceiver logic, and asynchronous select/enable circuitry to eliminate multiplexer glitches during real-time ↔ stored data transitions. Each bus (A and B) has dedicated clock (CAB/CBA), select (SAB/SBA), and output-enable (GAB/GBA) inputs enabling four distinct bus management modes.

The flow-through architecture allows concurrent data latching and bidirectional transfer without internal bus contention. Real-time transfer occurs when SAB/SBA = L; stored data transfer activates when SAB/SBA = H - with clock staggering required only when both registers load simultaneously under high-select mode.

Key Specifications

Pinout & Package

DW package is a 28-pin SOIC (Small Outline Integrated Circuit) with gull-wing leads, 300-mil body width, and center-aligned VCC (pins 21–22) and GND (pins 6–7, 9–10) for minimized high-speed switching noise.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74ACT11652DW, the 74ACT11837DW sacrifices bidirectional register control for lower gate count and cost, while SN74ACT11652DW offers identical performance with updated TI manufacturing traceability - making it the recommended long-term sourcing option.

Availability

74ACT11652DW is available at Aetrix Electronics and suitable for industrial backplane interfaces, real-time data acquisition systems, dual-processor memory coherency designs, and legacy bus protocol translation requiring stable component supply and guaranteed long-term availability.

Supply support for 74ACT11652DW 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 founded in 1930, specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

The 74ACT11652DW belongs to TI's advanced ACT (Advanced CMOS Technology) logic family, designed specifically for high-speed, low-noise, industrial-grade parallel bus interfacing with integrated storage and glitch-free multiplexing.

FAQ

What is the primary function of the 74ACT11652DW?

The 74ACT11652DW is an octal bus transceiver and register IC that enables bidirectional data transfer between two 8-bit buses (A and B) with optional storage in internal D flip-flops. It supports four fundamental operations: real-time A↔B transfer, stored-data A↔B transfer, independent A/B storage, and isolated bus hold - all controlled via dedicated enable (GAB/GBA) and select (SAB/SBA) inputs. Its design centers on deterministic timing and noise resilience in industrial bus systems.

Does the 74ACT11652DW support simultaneous real-time and stored data transfer?

No - the 74ACT11652DW does not perform simultaneous real-time and stored data transfer on the same bus pair. However, it allows independent configuration: one bus (e.g., A→B) can operate in real-time mode (SAB = L) while the other (B→A) uses stored data (SBA = H), provided clock edges are properly staggered per the datasheet's select-control timing rule. This enables flexible, non-blocking bus arbitration in multi-master systems.

What is the significance of center-pin VCC and GND in the 74ACT11652DW DW package?

The 74ACT11652DW DW package places VCC on pins 21–22 and GND on pins 6–7 and 9–10 - symmetrically centered along the long edge. This layout minimizes loop inductance and ground bounce during high-speed switching, directly reducing simultaneous switching noise (SSN) that could corrupt adjacent signal lines. It is a deliberate design choice for stable operation in dense, high-frequency PCB layouts where power integrity is critical.

Can unused control inputs on the 74ACT11652DW be left floating?

No - unused control inputs (GAB, GBA, CAB, CBA, SAB, SBA) on the 74ACT11652DW must be held at valid logic levels (VIL ≤ 0.8 V or VIH ≥ 2.0 V) to prevent undefined states, increased ICC, or unintended bus activity. The datasheet explicitly requires this per Note 3 under Recommended Operating Conditions. Floating inputs risk oscillation, excessive power draw, or spurious clocking of internal registers - compromising system reliability.

How does the 74ACT11652DW eliminate multiplexer glitches during mode transitions?

The 74ACT11652DW eliminates multiplexer glitches through dedicated hardware logic that decouples select (SAB/SBA) control from clock (CAB/CBA) and enable (GAB/GBA) paths. When transitioning between real-time and stored data modes, the internal state machine ensures no intermediate invalid output state occurs - unlike software-decoded muxes. This is confirmed in Figure 1 and the Function Table, where SAB/SBA transitions do not affect output validity during clock or enable changes.