Toshiba Semiconductor and Storage TC74ACT240F(EL,F)

Overview

TC74ACT240F from Toshiba Electronic Devices & Storage Corporation is an octal inverting 3-state bus buffer IC designed for memory address driving and data bus isolation in 5 V digital systems. It delivers 5.0 ns typical propagation delay, ±24 mA output drive at 4.5 V, and TTL-compatible input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V), operating across –40 °C to +85 °C.

For engineers reviewing the TC74ACT240F datasheet, TC74ACT240F pinout, TC74ACT240F application, or TC74ACT240F equivalent, key selection criteria include its inverting logic function, dual active-low output enables, SOP20 package compatibility with 74F240, and guaranteed 3-state leakage below ±5.0 µA over full temperature range.

Technical Context

The TC74ACT240F implements eight independent inverting buffer channels, each controlled by one of two shared active-low output enable inputs (1G̅ and 2G̅). Its C2MOS silicon gate process enables bipolar-speed performance while maintaining CMOS-level quiescent current (ICC ≤ 8.0 µA at 25 °C).

All inputs feature integrated ESD protection, and outputs support high-fanout 50 Ω transmission line driving per note in AC specs. Propagation delays are balanced (tPLH ≈ tPHL), and DC output voltage specifications are validated at both 4.5 V and 5.5 V supply rails.

Key Specifications

Pinout & Package

SOP20 (Small Outline Package, 20-pin, 300 mil width, 1.27 mm pitch) with gull-wing leads and 0.22 g typical weight.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TC74ACT240F, the 74ACT240 offers multi-source supply stability, while SN74ACT240N provides through-hole compatibility at the cost of larger footprint and marginally degraded AC performance - both retain full functional equivalence for inverting 3-state buffering.

Availability

TC74ACT240F is available at Aetrix Electronics and suitable for memory address drivers, industrial backplane interfaces, and legacy TTL system upgrades requiring stable component supply, long-term obsolescence management, and RoHS-compliant sourcing.

Supply support for TC74ACT240F 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

Toshiba Electronic Devices & Storage Corporation is a Japanese semiconductor manufacturer specializing in power devices, logic ICs, and storage solutions, with decades of experience in high-reliability industrial and automotive components.

The TC74ACT240F belongs to Toshiba's advanced CMOS logic family targeting 5 V systems needing TTL-compatible speed and CMOS efficiency - engineered specifically for bus buffering, address driving, and signal isolation in industrial control and computing infrastructure.

FAQ

What logic function does the TC74ACT240F implement?

The TC74ACT240F implements an octal inverting 3-state buffer function. Each of its eight channels accepts a logic input (A1–A8), inverts it, and presents the result at the corresponding output (Y1–Y8) when enabled. Two active-low output enables (1G̅ and 2G̅) independently control groups of four outputs. When either enable is high, its associated outputs enter high-impedance state - a core requirement for shared-bus architectures. This exact behavior is confirmed in the truth table and functional description of the official Toshiba datasheet.

Is the TC74ACT240F pin-compatible with the 74F240?

Yes, the TC74ACT240F is explicitly stated in Toshiba's documentation as pin- and function-compatible with the 74F240. Its SOP20 footprint matches the 74F240's SOIC-20 outline, and all pin assignments - including dual active-low enables, input/output pairing, and power/ground locations - align exactly. This allows direct substitution in existing 74F240-based designs without PCB modification, provided voltage and timing margins accommodate the TC74ACT240F's improved parameters like lower ICC and tighter delay balance.

What is the maximum operating temperature range for the TC74ACT240F?

TC74ACT240F is rated for continuous operation from –40 °C to +85 °C, as defined in Section 10 "Operating Ranges" of the Toshiba datasheet. This industrial-grade temperature range is validated across all DC and AC specifications, including output drive strength (±24 mA), propagation delay (≤9.0 ns max), and 3-state leakage (±5.0 µA max). The device meets this range under specified supply (4.5–5.5 V) and loading conditions, making it suitable for deployment in factory automation, motor drives, and outdoor embedded systems.

Does the TC74ACT240F support 50 Ω transmission line driving?

Yes, the TC74ACT240F is characterized for 50 Ω transmission line driving, as noted in the "Note 1" of Section 11.2 DC Characteristics. Its output drive capability of ±24 mA minimum at VCC = 4.5 V, combined with balanced tPLH/tPHL delays and low output impedance, enables clean signal integrity on controlled-impedance PCB traces. This capability is critical for minimizing reflections and ringing in high-speed address or data bus routing - a design requirement explicitly cited in Toshiba's application guidance for memory interface use cases.

What package type is used for the TC74ACT240F?

The TC74ACT240F uses the SOP20 (Small Outline Package, 20-pin) with 300 mil body width and 1.27 mm lead pitch. This surface-mount package is documented in the "Package Dimensions" section (page 6) of the Toshiba datasheet and confirmed by the marking "TC74ACT240F" on the device top. SOP20 provides compact footprint, automated assembly compatibility, and thermal performance suitable for industrial density layouts - distinct from PDIP or TSSOP variants of functionally similar parts.