Toshiba Semiconductor and Storage TC74LCX540FT(ELK,M

Overview

TC74LCX540FT(ELK,M) from Toshiba Electronic Devices & Storage Corporation is an inverting 3-state octal bus buffer optimized for 3.3-V systems with 5-V tolerant inputs and outputs. It features dual active-low output enables, 6.5 ns max propagation delay at 3.3 V, ±24 mA output drive, and operates across 1.65–3.6 V supply range. It serves as a level-shifting address/data driver in mixed-voltage memory interfaces.

For engineers reviewing the TC74LCX540FT(ELK,M) datasheet, TC74LCX540FT(ELK,M) pinout, TC74LCX540FT(ELK,M) application, or TC74LCX540FT(ELK,M) equivalent, key selection criteria include 5-V tolerance on all I/Os, dual OE control logic, guaranteed 3.3-V high-speed timing, and JEITA SOP-20 package compatibility with legacy 74-series footprints.

Technical Context

The TC74LCX540FT(ELK,M) implements a dual-enable, inverting 8-bit buffer architecture with independent high-impedance control per output group. Its input and output stages are designed with robust protection against static discharge and power-down leakage, enabling safe hot-swap operation in backplane and modular systems.

It supports bidirectional voltage translation between 3.3-V logic domains and 5-V peripherals without external level shifters. The device's AC characteristics-including 6.5 ns tpd (max), 8.5 ns tpZL/tpZH, and 7.5 ns tpLZ/tpHZ at 3.3 V-are fully characterized over −40°C to +85°C and validated for JEITA SOP-20 mechanical form factor.

Key Specifications

Pinout & Package

TC74LCX540FT(ELK,M) is supplied in JEITA-standard SOP-20 package (SOP20-P-300-1.27A), 12.8 mm × 7.6 mm body, 1.27 mm pitch, 2.25 mm height, 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 TC74LCX540FT(ELK,M), the 74LVC541APW offers faster speed but lacks 5-V tolerance and inversion; SN74LVTH16244 provides double width and same I/O robustness but requires larger PCB area and different enable logic.

Availability

TC74LCX540FT(ELK,M) is available at Aetrix Electronics and suitable for memory interface design, industrial PLC expansion, automated test equipment signal conditioning, and automotive diagnostic subsystems requiring stable component supply and long-term obsolescence management.

Supply support for TC74LCX540FT(ELK,M) 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 designs and manufactures high-reliability semiconductor components for industrial, automotive, and computing applications, with emphasis on low-power, mixed-voltage interoperability.

The TC74LCX540FT(ELK,M) belongs to Toshiba's LCX low-voltage CMOS logic family, engineered specifically for seamless voltage-domain bridging in 3.3-V systems interfacing with legacy 5-V infrastructure.

FAQ

What is the maximum operating frequency supported by TC74LCX540FT(ELK,M)?

The TC74LCX540FT(ELK,M) does not specify a maximum clock frequency directly, but its 6.5 ns (max) propagation delay at 3.3 V implies reliable operation up to approximately 100 MHz for address/data strobe timing. System-level frequency limits depend on trace length, load capacitance, and setup/hold margins-not the IC alone. TC74LCX540FT(ELK,M) is typically deployed in asynchronous or low-to-moderate-speed synchronous bus applications rather than high-frequency clock domains.

Does TC74LCX540FT(ELK,M) support hot-swap insertion?

Yes-TC74LCX540FT(ELK,M) includes power-down protection on all inputs and outputs, and its 5-V tolerant I/O structure allows safe connection to live 5-V buses before VCC ramp-up. Input diode current ratings (±50 mA) and off-state leakage (<5 µA) ensure no latch-up or damage during partial power sequencing. This makes TC74LCX540FT(ELK,M) suitable for modular backplane and field-replaceable unit designs.

Is TC74LCX540FT(ELK,M) RoHS compliant?

Yes-TC74LCX540FT(ELK,M) meets EU RoHS Directive 2011/65/EU requirements for restricted substances. Toshiba confirms lead-free terminations and halogen-free molding compound for this JEITA SOP-20 variant. Full compliance documentation, including SDoC and material declarations, is available through Toshiba's official product portal and authorized distributors.

Can TC74LCX540FT(ELK,M) drive standard TTL loads?

No-TC74LCX540FT(ELK,M) is not designed to drive legacy TTL (e.g., 74LS) loads directly. Its VOH minimum is VCC−0.2 V (e.g., 3.1 V at 3.3 V), which exceeds TTL VIH (2.0 V), but its VOL maximum is 0.55 V at 24 mA-higher than TTL VIL (0.8 V). While it may function marginally, Toshiba specifies compatibility only with CMOS loads (including 74AC/VHC/HC families), not bipolar TTL. Use TC74LCX540FT(ELK,M) with CMOS or LVTTL interfaces only.

What is the thermal resistance (θJA) of TC74LCX540FT(ELK,M)?

Toshiba does not publish θJA for TC74LCX540FT(ELK,M) in the provided datasheet. However, based on JEITA SOP-20 package dimensions (12.8 × 7.6 mm, 1.27 mm pitch) and typical thermal performance of similar devices, θJA is estimated at ~120°C/W under standard 1-inch² 2-layer PCB conditions. For thermal design, assume maximum power dissipation of 180 mW (absolute max) and derate linearly above 25°C ambient using the published operating temperature range (−40°C to +85°C). TC74LCX540FT(ELK,M) is not intended for continuous high-power operation.