onsemi 74ABT2244CSJ

Overview

74ABT2244CSJ from Fairchild Semiconductor is an octal non-inverting buffer/line driver with integrated 25Ω series output resistors, designed for driving capacitive loads in memory, address, clock, and bus-oriented systems. It operates at 4.5V–5.5V, delivers 32mA HIGH drive and 15mA LOW drive, and features dual active-low output enables (OE1/OE2) for independent 4-bit group control.

For engineers reviewing the 74ABT2244CSJ datasheet, pinout, applications, or equivalent options, key selection criteria include guaranteed latchup protection, hot-insertion capability, glitch-free high-impedance during power sequencing, and elimination of external termination resistors due to on-die 25Ω series resistors.

Technical Context

The 74ABT2244CSJ implements two independent 4-bit buffered paths, each controlled by a dedicated active-low output enable (OE1 for I0–I3/O0–O3; OE2 for I4–I7/O4–O7). Its ABT logic family ensures TTL-compatible input thresholds (VIH = 2.0V, VIL = 0.8V) and fast propagation delays (tPLH/tPHL ≤ 3.9ns at 5V).

Each output integrates a 25Ω series resistor to dampen signal reflections on transmission lines, reducing ringing without requiring external components. The device maintains high-impedance outputs during power-up/down cycles and supports nondestructive hot insertion per JEDEC JESD78 compliance.

Key Specifications

Pinout & Package

74ABT2244CSJ is housed in a 20-lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm wide (Package Number M20D), with standard 1.27mm pitch and gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ABT2244N and 74LVT2244PW, the 74ABT2244CSJ uniquely combines 5V operation, integrated 25Ω termination, and SOP packaging - delivering optimal signal integrity and layout simplicity for industrial 5V bus interfaces without redesigning termination networks.

Availability

74ABT2244CSJ is available at Aetrix Electronics and suitable for memory subsystems, clock distribution networks, hot-swappable backplanes, and industrial control bus interfaces requiring stable component supply and long-term industrial lifecycle support.

Supply support for 74ABT2244CSJ 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

Fairchild Semiconductor was a U.S.-based semiconductor company specializing in analog and mixed-signal ICs, acquired by ON Semiconductor in 2016; its ABT logic family remains widely supported in industrial and legacy designs.

The 74ABT2244CSJ belongs to Fairchild's Advanced BiCMOS Technology (ABT) logic series, engineered for high-speed, high-drive 5V TTL-compatible bus interface applications with enhanced robustness and signal integrity.

FAQ

What is the function of the 25Ω series resistors in the 74ABT2244CSJ outputs?

The 25Ω series resistors in each output of the 74ABT2244CSJ are integrated on-die to provide source termination for transmission lines, reducing signal reflections and overshoot without requiring external components. This design simplifies PCB layout, saves board space, and improves signal integrity on unterminated or stub-loaded traces commonly found in memory and bus applications. The 74ABT2244CSJ achieves this while maintaining full compatibility with standard ABT logic performance metrics.

Does the 74ABT2244CSJ support hot insertion, and how is it implemented?

Yes, the 74ABT2244CSJ supports nondestructive hot insertion per JEDEC JESD78 Class II. This is achieved through internal circuitry that isolates I/O pins during power-up/down transients and prevents latchup under biased conditions. The device tolerates ±300mA latchup current and maintains high-impedance outputs until VCC stabilizes, allowing safe insertion into live backplanes. This behavior is intrinsic to the 74ABT2244CSJ's ABT process and architecture, not dependent on external circuitry.

What are the absolute maximum ratings for VCC and input voltage on the 74ABT2244CSJ?

The 74ABT2244CSJ has an absolute maximum VCC rating of –0.5V to +7.0V and an absolute maximum input voltage (VIN) of –0.5V to +7.0V. These stress ratings define the limits beyond which permanent damage may occur; operation outside the recommended range (VCC = +4.5V to +5.5V, VIN = –0.5V to VCC + 0.5V) is not advised. The 74ABT2244CSJ also includes input clamp diodes rated to –1.2V (IIN = –18mA) and supports up to 10V overvoltage latchup immunity on I/O pins.

How does the dual output enable (OE1/OE2) architecture of the 74ABT2244CSJ improve system design flexibility?

The 74ABT2244CSJ uses two independent active-low output enables (OE1 for O0–O3, OE2 for O4–O7) to allow selective activation of two 4-bit groups. This enables partial bus driving, dynamic power reduction, and hierarchical control in multi-segment systems - for example, enabling only memory address bits [3:0] during decode and [7:4] during data transfer. The 74ABT2244CSJ's pinout and logic ensure zero contention between groups, making it ideal for segmented bus architectures without additional logic.

Is the 74ABT2244CSJ pin-compatible with other packages in the same family, such as 74ABT2244CSC or 74ABT2244CMSA?

No, the 74ABT2244CSJ is not pin-compatible with 74ABT2244CSC (SOIC, M20B) or 74ABT2244CMSA (SSOP, MSA20), despite sharing identical logic functionality and pin assignments. While all variants use 20-pin configurations with identical signal mapping (I0–I7, O0–O7, OE1, OE2, VCC, GND), their physical footprints differ: CSJ uses EIAJ TYPE II SOP (5.3mm width), CSC uses JEDEC MS-013 SOIC (7.5mm width), and CMSA uses SSOP (5.3mm width but finer 0.65mm pitch). PCB layout must match the specific package dimensions of the 74ABT2244CSJ.