Texas Instruments CY74FCT2240CTSOC

Overview

CY74FCT2240CTSOC from Texas Instruments is an octal noninverting buffer/line driver with 3-state outputs, designed for memory address, clock, and bus-oriented transmission in TTL/CMOS/NMOS systems. It features on-chip 25-Ω series output resistors, I_off partial-power-down support, 4.1 ns max propagation delay, ±15 mA output drive, and SOIC-20 package.

For engineers reviewing the CY74FCT2240CTSOC datasheet, CY74FCT2240CTSOC pinout, CY74FCT2240CTSOC application, or CY74FCT2240CTSOC equivalent, key selection criteria include 3-state control timing (t_PZH/t_PLZ ≤ 5.2 ns), I_off leakage (< ±1 µA at V_CC = 0 V), 25-Ω integrated termination, TTL-compatible input thresholds (V_IL = 0.8 V, V_VIH = 2.0 V), and SOIC-20 thermal performance (θ_JA = 58°C/W).

Technical Context

This device implements dual 4-bit noninverting buffers with independent 3-state enable controls (OEA and OEB), supporting bidirectional bus interfacing without external logic. Each output integrates a 25-Ω series resistor to suppress transmission-line reflections-eliminating discrete termination components while maintaining signal integrity at high edge rates.

The I_off circuitry actively disables outputs during power-down, blocking reverse current flow when V_CC = 0 V and preventing damage to powered system sections. Input hysteresis (V_hys = 0.2 V) and ESD protection (2000-V HBM, 200-V MM, 1000-V CDM) ensure robust operation in mixed-voltage industrial environments.

Key Specifications

Pinout & Package

Package: SOIC-20 (SO), body size 7.5 mm × 12.8 mm, 1.27 mm pitch, JEDEC MS-013AC compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74F240N and 74ACT240SCX, CY74FCT2240CTSOC uniquely combines integrated 25-Ω termination, I_off, and 4.1 ns speed in SOIC-20-reducing BOM count and enabling robust hot-swap operation without layout redesign.

Availability

CY74FCT2240CTSOC is available at Aetrix Electronics and suitable for memory address buffering, clock distribution networks, and industrial bus transceiver interfaces requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant sourcing.

Supply support for CY74FCT2240CTSOC 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 delivering analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

CY74FCT2240CTSOC belongs to the FCT logic family-designed specifically for high-speed, low-noise, TTL-compatible digital interfacing in mission-critical industrial and telecom infrastructure.

FAQ

What is the maximum operating temperature range for CY74FCT2240CTSOC?

CY74FCT2240CTSOC is rated for operation from –40°C to +85°C ambient temperature, making it suitable for industrial control cabinets, outdoor telecom equipment, and factory automation systems where extended thermal margins are required. This range is validated per TI's recommended operating conditions and supported by its SOIC package's 58°C/W thermal resistance.

Does CY74FCT2240CTSOC support hot-swap or partial-power-down operation?

Yes, CY74FCT2240CTSOC includes I_off circuitry that disables outputs when V_CC = 0 V, limiting reverse current to ±1 µA. This allows safe insertion/removal in live backplanes or modular systems. The feature is fully specified in TI's datasheet and does not require external biasing-CY74FCT2240CTSOC remains functional after power cycling without latch-up risk.

How does the 25-Ω on-chip series resistor in CY74FCT2240CTSOC improve signal integrity?

The 25-Ω resistor in CY74FCT2240CTSOC is placed in series with each output driver to match typical PCB trace impedances (50–75 Ω), reducing reflections that cause ringing and false triggering. Measured ROUT = 20–40 Ω (typ 25 Ω) ensures consistent termination without discrete components-directly lowering EMI and improving timing margin in high-speed address or clock lines driven by CY74FCT2240CTSOC.

What are the enable timing specifications for CY74FCT2240CTSOC's 3-state outputs?

CY74FCT2240CTSOC specifies t_PZH and t_PLZ ≤ 5.2 ns (max) from OEA/OEB transition to output high-impedance state, and t_PHZ/t_PLZ ≤ 5.2 ns (max) for disable timing. These values ensure precise bus arbitration in multiplexed systems-critical when CY74FCT2240CTSOC shares data lines with other drivers in real-time control applications.

Is CY74FCT2240CTSOC pin-compatible with older 74LS240 or 74F240 devices?

CY74FCT2240CTSOC is functionally and pin-compatible with 74LS240 and 74F240 in SOIC-20 packages, sharing identical pin assignments for inputs, outputs, enables, V_CC, and GND. However, CY74FCT2240CTSOC adds integrated 25-Ω resistors and I_off-features absent in legacy parts-making it a direct upgrade path without PCB changes.