Texas Instruments CY74FCT2240TSOCG4

Overview

CY74FCT2240TSOCG4 from Texas Instruments is an octal noninverting buffer/line driver with 3-state outputs, 25-Ω on-chip series termination resistors per output, 8 ns max propagation delay, ±15 mA output drive, and Ioff support for partial-power-down operation. It serves as a memory address driver, clock driver, or bus transmitter in TTL/CMOS/NMOS interfaced systems.

For engineers reviewing the CY74FCT2240TSOCG4 datasheet, CY74FCT2240TSOCG4 pinout, CY74FCT2240TSOCG4 application, or CY74FCT2240TSOCG4 equivalent, key selection criteria include 3-state control timing (tPZH/tPLZ ≤9.5 ns), 25-Ω integrated output impedance, Ioff leakage <±1 µA at VCC = 0 V, and SOIC-20 package compatibility with legacy FCT logic families.

Technical Context

This device implements dual 4-bit noninverting buffers with independent 3-state enable controls (OEA and OEB), each driving four outputs (OA0–OA3 and OB0–OB3) with edge-rate control circuitry to suppress transmission-line reflections. The 25-Ω series resistors are integrated directly at each output terminal, eliminating external termination components.

It operates over –40°C to +85°C with 4.75–5.25 V supply, supports TTL-level inputs (VIH = 2 V, VIL = 0.8 V), delivers VOH ≥2.4 V at –15 mA and VOL ≤0.55 V at 12 mA, and features Ioff protection that disables outputs and limits backflow current when VCC = 0 V.

Key Specifications

Pinout & Package

Package: SOIC-20 (SO), body size 7.5 mm × 12.8 mm, standard JEDEC MS-013AC footprint, RoHS-compliant NiPdAu lead finish, MSL Level-2-260°C-1 year.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74FCT2240CTSOCT and 74ACT240SCX, CY74FCT2240TSOCG4 offers optimal balance of reflection suppression, Ioff safety, and legacy TTL compatibility - making it the preferred choice for retrofitting or maintaining industrial bus interfaces where signal integrity and power-down robustness are critical.

Availability

CY74FCT2240TSOCG4 is available at Aetrix Electronics and suitable for memory address buffering, clock distribution, and bus-oriented transmitter/receiver applications requiring stable component supply across extended industrial temperature ranges and long production lifecycles.

Supply support for CY74FCT2240TSOCG4 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 headquartered in Dallas, Texas, specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

CY74FCT2240TSOCG4 belongs to TI's FCT logic family - engineered for high-speed, low-noise 5-V TTL-compatible digital interfacing with emphasis on bus integrity, power-down safety, and drop-in replacement for legacy bipolar logic.

FAQ

What is the maximum operating temperature range for CY74FCT2240TSOCG4?

CY74FCT2240TSOCG4 is rated for operation from –40°C to +85°C ambient temperature. This industrial-grade range ensures reliable performance in factory automation controllers, motor drives, and outdoor communication equipment where thermal cycling and sustained elevated temperatures occur. The SOIC-20 package has a θJA of 58°C/W, supporting continuous operation within this range under typical PCB copper pour conditions.

Does CY74FCT2240TSOCG4 support hot-swap or partial-power-down operation?

Yes, CY74FCT2240TSOCG4 includes Ioff circuitry that actively disables outputs and limits reverse current to ±1 µA when VCC = 0 V, even with input voltages up to 4.5 V. This feature makes CY74FCT2240TSOCG4 suitable for hot-pluggable modules, modular backplanes, and systems requiring graceful power sequencing - unlike standard TTL or ACT devices that risk latch-up or damage under such conditions.

How does the 25-Ω on-chip series resistor in CY74FCT2240TSOCG4 improve signal integrity?

The 25-Ω resistor integrated at each output of CY74FCT2240TSOCG4 matches typical PCB trace impedances (50–75 Ω) in source-series termination configurations. This minimizes signal reflections, reduces overshoot/ringing by up to 60%, and eliminates the need for 16 discrete 0402/0603 resistors - directly improving timing margin and electromagnetic compatibility in high-density routing scenarios.

What are the enable timing specifications for CY74FCT2240TSOCG4's 3-state outputs?

CY74FCT2240TSOCG4 specifies tPZH and tPLZ (enable-to-output-high and enable-to-output-low) at ≤9.5 ns max, and tPHZ and tPZL (disable-to-high-impedance) at ≤9.5 ns max, measured under CL = 50 pF. These values ensure fast, predictable bus release and acquisition - critical for meeting 80 ns minimum bus turnaround in legacy 8086/80286-style systems and modern FPGA-to-peripheral interfaces.

Is CY74FCT2240TSOCG4 pin-compatible with older 74F240 or 74ACT240 devices?

CY74FCT2240TSOCG4 is functionally and pin-compatible with 74F240 and 74ACT240 in SOIC-20 packages, sharing identical pin assignments for inputs (DA0–DA3, DB0–DB3), outputs (OA0–OA3, OB0–OB3), enables (OEA, OEB), VCC, and GND. However, CY74FCT2240TSOCG4 adds integrated 25-Ω resistors and Ioff - requiring no layout change but enabling improved noise immunity and power-down safety over those predecessors.