Texas Instruments SN64BCT25244DW

Overview

SN64BCT25244DW from Texas Instruments is a 25-Ω octal 3-state buffer/line driver optimized for incident-wave switching on 25-Ω transmission lines, delivering 188-mA sink current (IOL), 4.5–5.5-V supply operation, and high-impedance state during power-up/down below ~3 V. It serves as a memory address driver, clock driver, or bus transceiver in high-density digital systems.

For engineers reviewing the SN64BCT25244DW datasheet, SN64BCT25244DW pinout, SN64BCT25244DW application, or SN64BCT25244DW equivalent, key selection criteria include 25-Ω line driving capability, distributed VCC/GND noise suppression, −40°C to 85°C industrial temperature range, BiCMOS low ICCZ quiescent current, and SOIC-24 (DW) package compatibility with legacy DIP footprints.

Technical Context

This device implements dual 4-bit noninverting buffers with independent output-enable controls (1OE, 2OE), each enabling/disabling four Y outputs based on active-low logic. Its BiCMOS architecture combines bipolar speed and CMOS input impedance to achieve sub-6 ns propagation delay (tPLH/tPHL) and <10 ns enable/disable timing (tPZH/tPHZ) at 5 V.

Designed specifically for incident-wave switching, it drives 25-Ω transmission lines without termination by sourcing/sinking sufficient current to match line impedance during signal launch. Distributed VCC and GND pins across the SOIC-24 package reduce simultaneous switching noise, improving signal integrity in dense bus environments.

Key Specifications

Pinout & Package

SN64BCT25244DW uses a 24-pin SOIC (Small-Outline Integrated Circuit) package with DW drawing code, RoHS-compliant NIPDAU finish, and moisture sensitivity level (MSL) 1 (unlimited floor life at ≤30°C/60% RH).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal 3-state buffer applications.

Compared with SN74BCT244N and SN64BCT25244NT, the SN64BCT25244DW uniquely delivers 25-Ω line driving in a space-constrained SOIC-24 package with industrial temperature support and superior noise immunity via distributed power pins - making it optimal for high-reliability, high-speed bus interfaces where layout density and signal fidelity are critical.

Availability

SN64BCT25244DW is available at Aetrix Electronics and suitable for memory address buffering, clock distribution networks, and bus transceiver interfaces requiring stable component supply, long-term industrial temperature support, and RoHS-compliant packaging.

Supply support for SN64BCT25244DW 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 company founded in 1930, specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

The BCT (Bipolar-CMOS Transistor) logic family, including SN64BCT25244DW, was engineered to merge TTL speed with CMOS input characteristics for high-drive, low-noise bus interface applications in demanding industrial environments.

FAQ

What is the primary function of the SN64BCT25244DW in a digital system?

The SN64BCT25244DW functions as an octal noninverting 3-state buffer and line driver, primarily used to drive 25-Ω transmission lines in memory address, clock, and bus applications. Its 188-mA sink current enables incident-wave switching without external termination, and its dual output-enable inputs (1OE, 2OE) allow independent control of two 4-bit output groups. This makes the SN64BCT25244DW ideal for high-density, noise-sensitive digital interconnects where signal integrity and timing precision are critical.

Does the SN64BCT25244DW support hot-plug or live-insertion scenarios?

Yes - the SN64BCT25244DW supports safe hot-plug operation due to its guaranteed high-impedance state during power-up and power-down when VCC falls below approximately 3 V. This feature prevents bus contention and back-driving of powered subsystems when the device is inserted or removed under partial bias. Additionally, its ESD protection (>2000 V HBM) and input clamp current rating (−18 mA) enhance resilience against transient coupling during insertion events, making the SN64BCT25244DW suitable for modular backplane and field-replaceable unit designs.

Can the SN64BCT25244DW replace older 74-series TTL buffers like the 74LS244?

No - the SN64BCT25244DW is not a direct functional or pinout replacement for the 74LS244. While both are octal buffers, the SN64BCT25244DW has a 24-pin SOIC/DIP package (vs. 20-pin for 74LS244), higher drive strength (188 mA vs. ~24 mA), 25-Ω line optimization, and different pin assignments (e.g., separate VCC/GND distribution). The SN64BCT25244DW also requires strict adherence to its 4.5–5.5-V supply range and active-low OE logic. Substituting it for a 74LS244 would require PCB layout changes and timing validation; the SN64BCT25244DW is best applied where its specific 25-Ω drive and noise-suppression features are needed.

What is the significance of distributed VCC and GND pins in the SN64BCT25244DW package?

Distributed VCC and GND pins - located at pins 2, 5, 8, 11, 16, 20 (GND) and 18, 21 (VCC) - minimize simultaneous switching noise by reducing inductance in local power delivery paths. When multiple outputs switch concurrently, localized current spikes are contained within shorter loop areas, lowering ground bounce and supply droop. This design directly improves signal integrity and timing margin in high-speed bus applications. For the SN64BCT25244DW, this architecture is essential to maintain sub-6 ns propagation delay consistency and prevent false triggering in adjacent logic, especially in dense memory or clock distribution layouts.

Is the SN64BCT25244DW compatible with 3.3-V logic systems?

No - the SN64BCT25244DW is specified only for 4.5–5.5-V operation and is not 3.3-V tolerant. Its input thresholds (VIH ≥ 2 V, VIL ≤ 0.8 V) and output voltage levels (VOH ≥ 2 V at −80 mA, VOL ≤ 0.7 V at 188 mA) are designed for 5-V TTL compatibility. Driving its inputs from 3.3-V logic may result in marginal or unreliable switching, and applying 3.3-V VCC violates the absolute maximum rating (VCC min = −0.5 V, but recommended min = 4.5 V). For 3.3-V systems, TI recommends logic families such as AVC or LVC; the SN64BCT25244DW must be used strictly within its 5-V domain.