onsemi 74ABT240CMSA

Overview

74ABT240CMSA from Fairchild Semiconductor is an inverting octal buffer/line driver with 3-STATE outputs, designed for memory address and clock distribution, bus transceiver applications, and high-density PCB layout optimization. It operates at 4.5–5.5 V, delivers 64 mA sink / 32 mA source drive strength, and features guaranteed latchup protection and nondestructive hot insertion capability.

For engineers reviewing the 74ABT240CMSA datasheet, pinout, applications, or equivalent options, this page provides verified functional identity, SSOP-20 package mapping, real-world timing (tPLH/tPHL ≤ 4.8 ns @ CL=50 pF), DC electrical specs (VIL=0.8 V, VOH=2.5 V @ IOH=32 mA), and two validated alternative parts for bus interface design.

Technical Context

The 74ABT240CMSA implements dual independent 3-STATE enable control (OE1/OE2) for two groups of four inverting buffers (I0–I3 → O0–O3; I4–I7 → O4–O7), supporting bidirectional bus isolation. Its ABT logic family ensures TTL-compatible input thresholds and enhanced noise immunity across industrial temperature range (–40°C to +85°C).

It guarantees glitch-free high-impedance state during power-up/power-down sequences and withstands overvoltage conditions up to 10 V on I/O pins without latchup, meeting JEDEC J-STD-020B Pb-free compliance in its MSA20 SSOP package.

Key Specifications

Pinout & Package

74ABT240CMSA is housed in a 20-lead Shrink Small Outline Package (SSOP), JEDEC MO-150 compliant, 5.3 mm wide, with 0.65 mm lead pitch and exposed pad not present.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74ABT240DBR and 74LVT240PW, the 74ABT240CMSA uniquely combines 5 V operation, 64 mA drive, and certified hot-insertion capability-making it the sole choice for industrial backplane and memory buffering where voltage compatibility and ruggedness are mandatory.

Availability

74ABT240CMSA 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 lifecycle support, and Pb-free compliance.

Supply support for 74ABT240CMSA 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 analog and power IC designer acquired by ON Semiconductor in 2016; its ABT logic family remains widely deployed in industrial and telecom infrastructure.

The 74ABT240CMSA belongs to Fairchild's Advanced BiCMOS Technology (ABT) logic series, engineered specifically for high-speed, high-drive 5 V bus interface and memory subsystem applications demanding reliability under dynamic thermal and electrical stress.

FAQ

What is the operating voltage range for the 74ABT240CMSA?

The 74ABT240CMSA operates over a supply voltage range of 4.5 V to 5.5 V. This range ensures full functionality and specification compliance-including output drive strength, propagation delay, and input threshold behavior-across variations in 5 V rail tolerance and temperature. Operation outside this range may result in undefined logic states or degraded parametric performance.

Does the 74ABT240CMSA support hot insertion?

Yes, the 74ABT240CMSA supports nondestructive hot insertion as a guaranteed feature per its datasheet. This capability allows safe connection to a live backplane or powered bus without causing latchup, I/O damage, or system reset-enabled by internal circuitry that prevents forward biasing of parasitic structures during partial power application.

What is the function of OE1 and OE2 on the 74ABT240CMSA?

OE1 and OE2 are active-low 3-STATE enable inputs on the 74ABT240CMSA. OE1 controls outputs O0–O3, and OE2 controls O4–O7. When asserted low, the respective group of outputs drives inverted input signals; when high, those outputs enter high-impedance state-enabling independent bus arbitration and multi-drop topology support.

What package type does the 74ABT240CMSA use?

The 74ABT240CMSA uses a 20-lead Shrink Small Outline Package (SSOP), designated JEDEC MO-150, 5.3 mm wide, with 0.65 mm lead pitch. Its MSA20 package code distinguishes it from SOIC (M20B) and TSSOP (MTC20) variants of the same device family, and requires corresponding PCB land pattern per Fairchild's mechanical drawings.

How does the 74ABT240CMSA handle power-up sequencing?

The 74ABT240CMSA ensures glitch-free bus loading during power-up and power-down by maintaining all outputs in high-impedance state until VCC reaches valid operating level and input enable states stabilize. This behavior eliminates transient contention on shared buses and is guaranteed across the full –40°C to +85°C temperature range without external reset circuitry.