Renesas 54FCT245ATDB

Overview

54FCT245ATDB from Renesas Electronics (formerly IDT) is a military-grade octal bidirectional transceiver in CERDIP package, operating from –55°C to +125°C at 5.0V ±10%. It provides TTL-compatible I/O (VOH = 2.4V min, VOL = 0.55V max), high-drive outputs (–15mA IOH, 64mA IOL), and 3-state control via OE and T/R pins for bus isolation in harsh-environment avionics data links.

For engineers reviewing the 54FCT245ATDB datasheet, 54FCT245ATDB pinout, 54FCT245ATDB application, or 54FCT245ATDB equivalent, key selection criteria include MIL-STD-883 Class B compliance, CERDIP packaging for hermetic reliability, propagation delay ≤4.9ns (A→B/B→A), output enable/disable timing ≤6.5ns, and true TTL input/output voltage thresholds under extended temperature stress.

Technical Context

The 54FCT245ATDB implements asynchronous bidirectional data flow between two 8-bit buses using a single active-low Output Enable (OE) and active-high Transmit/Receive (T/R) control logic. Direction is determined solely by T/R state: high enables A→B transfer; low enables B→A transfer.

All 16 I/O pins (A0–A7, B0–B7) are 3-state capable with leakage ≤±1µA and input capacitance ≤10pF. The device meets JEDEC Std 18 and supports live insertion via power-off disable outputs, ensuring safe hot-swap operation in mission-critical backplane systems.

Key Specifications

Pinout & Package

54FCT245ATDB is supplied in a 20-pin CERDIP (CD20) hermetic ceramic dual in-line package, rated for extended thermal cycling and high-reliability environments.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal bidirectional transceiver applications.

Compared with 54FCT245TDB and 54FCT245CTDB, the 54FCT245ATDB delivers the optimal trade-off of sub-5ns latency, MIL-qualified reliability, and proven field performance in time-critical avionics interfaces-making it the preferred choice where deterministic timing and hermetic packaging are non-negotiable.

Availability

54FCT245ATDB is available at Aetrix Electronics and suitable for avionics data bus interface, secure military backplane, and tactical vehicle control system applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 54FCT245ATDB 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

Renesas Electronics Corporation is a global semiconductor leader delivering microcontrollers, analog, power, and connectivity solutions for automotive, industrial, infrastructure, and IoT applications.

The 54FCT245ATDB belongs to Renesas' legacy IDT military logic family, engineered specifically for high-reliability, extended-temperature data path interfacing in defense and aerospace platforms.

FAQ

What is the maximum propagation delay of the 54FCT245ATDB under military temperature conditions?

The 54FCT245ATDB has a maximum propagation delay (tPLH/tPHL) of 4.9ns under industrial conditions and 4.9ns is also specified for the "AT" speed grade in military temperature range (–55°C to +125°C) per the switching characteristics table. This value is measured at CL = 50pF and RL = 500Ω, confirming its suitability for high-speed synchronous bus bridging in demanding environments where timing predictability is critical. The 54FCT245ATDB maintains this performance across its full operating range without derating.

Does the 54FCT245ATDB support live insertion, and how is this implemented?

Yes, the 54FCT245ATDB supports live insertion through its power-off disable outputs feature. When VCC drops below operational threshold, all I/O pins (A0–A7, B0–B7) automatically enter high-impedance state regardless of OE or T/R states. This prevents bus contention during hot-swap operations in modular avionics racks. The 54FCT245ATDB achieves this via internal circuitry that detects VCC loss and forces output drivers into tri-state mode-verified per MIL-STD-883 test methods.

What package type is used for the 54FCT245ATDB, and why is it suited for military applications?

The 54FCT245ATDB is packaged in a 20-pin CERDIP (CD20) ceramic dual in-line package. This hermetic ceramic construction provides superior moisture resistance, thermal stability, and mechanical ruggedness compared to plastic packages. Its coefficient of thermal expansion closely matches PCB substrates used in aerospace assemblies, minimizing solder joint fatigue during thermal cycling. The 54FCT245ATDB's CERDIP package is explicitly qualified to MIL-STD-883 Class B, making it ideal for deployment in launch vehicles, radar systems, and other mission-critical platforms.

How does the 54FCT245ATDB ensure compatibility with legacy TTL systems?

The 54FCT245ATDB guarantees true TTL input and output compatibility via specified voltage thresholds: VIH ≥2.0V (min), VIL ≤0.8V (max), VOH ≥2.4V (min at –15mA), and VOL ≤0.55V (max at +64mA). These values exceed standard TTL requirements and are validated across the full –55°C to +125°C range. The 54FCT245ATDB also features low input leakage (≤±1µA) and CMOS power efficiency while maintaining TTL-level signaling-enabling drop-in replacement in aging 5V systems without redesign.

What are the absolute maximum ratings for the 54FCT245ATDB's I/O terminals?

The 54FCT245ATDB specifies absolute maximum terminal voltages of –0.5V to +7.0V for inputs and VCC terminals, and –0.5V to VCC+0.5V for output and I/O terminals. DC output current is rated from –60mA to +120mA. These limits define safe handling boundaries during assembly, testing, and transient events. Exceeding them-even momentarily-may cause permanent damage. The 54FCT245ATDB's design incorporates clamp diodes (VIK = –0.7V typical) to protect against electrostatic discharge, consistent with MIL-STD-883 requirements.