Renesas 74FCT244ATPYG

Overview

74FCT244ATPYG from Renesas Electronics (formerly IDT) is a fast CMOS octal buffer/line driver with 3-state outputs, designed for memory and address bus driving, clock distribution, and bidirectional data transmission in industrial systems. It features true TTL input/output compatibility (VOH = 3.3 V typ., VOL = 0.3 V typ.), high drive capability (–15 mA IOH, 64 mA IOL), and operates across –40°C to +85°C.

For engineers reviewing the 74FCT244ATPYG datasheet, 74FCT244ATPYG pinout, 74FCT244ATPYG application, or 74FCT244ATPYG equivalent, key selection criteria include its dual enable-controlled 3-state operation, low leakage (≤1 µA max), JEDEC 18 compliance, and TSSOP-20 package suitability for high-density PCB layouts.

Technical Context

The 74FCT244ATPYG implements two independent 4-bit non-inverting buffers, each controlled by an active-low 3-state enable (OEA, OEB). Its dual-metal CMOS process ensures TTL-compatible input thresholds (VIH = 2.0 V min, VIL = 0.8 V max) and rail-to-rail output swing under load.

Propagation delays are tightly specified: tPLH/tPHL ≤ 4.1 ns (industrial, CL = 50 pF, RL = 500 Ω), with enable/disable times (tPZH/tPHZ/tPZL/tPLZ) ≤ 6.2 ns. The device supports live insertion via power-off disable outputs and meets MIL-STD-883 Class B for military-grade reliability variants.

Key Specifications

Pinout & Package

74FCT244ATPYG is packaged in a 20-pin Thin Shrink Small Outline Package (TSSOP), 4.4 mm width, 0.65 mm pitch, with exposed pad not present. Pinout follows JEDEC MS-013AC standard for 20-pin TSSOP.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74F244N and 74LCX244MTCX, the 74FCT244ATPYG uniquely balances 5 V TTL compatibility, industrial temperature operation, low ICC (1 mA max), and live-insertion capability - making it optimal for long-lifecycle industrial controllers where supply voltage stability and field-replaceability matter.

Availability

74FCT244ATPYG is available at Aetrix Electronics and suitable for industrial automation, legacy system upgrades, and test equipment requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant TSSOP packaging.

Supply support for 74FCT244ATPYG 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 timing solutions for automotive, industrial, infrastructure, and IoT applications.

The 74FCT244ATPYG belongs to Renesas' legacy IDT fast CMOS logic family, engineered specifically for high-reliability 5 V digital interfacing in industrial control, instrumentation, and military-aerospace subsystems.

FAQ

What is the maximum operating frequency supported by the 74FCT244ATPYG?

The 74FCT244ATPYG does not specify a maximum clock frequency in its datasheet because it is an asynchronous buffer. Its usable frequency depends on system-level timing: with ≤4.1 ns propagation delay and ≤6.2 ns enable/disable times, it reliably supports data rates up to ~250 Mbps in point-to-point configurations and bus frequencies up to 20–25 MHz in loaded multi-drop topologies. The 74FCT244ATPYG performance is validated under CL = 50 pF and RL = 500 Ω conditions per JEDEC standards.

Does the 74FCT244ATPYG support 3.3 V logic inputs?

No, the 74FCT244ATPYG is designed for 5 V operation only and requires VIH ≥ 2.0 V (min) for HIGH recognition - compatible with 3.3 V CMOS outputs only if they guarantee VOH ≥ 2.4 V under load. It is not 5 V-tolerant in 3.3 V mode; applying 3.3 V to VCC violates its 5.0 V ±5% specification. The 74FCT244ATPYG must be powered from a regulated 5 V rail to meet all AC/DC specifications.

Can both output enable pins (OEA and OEB) be tied together in the 74FCT244ATPYG?

Yes, OEA and OEB may be connected to a common control signal to simultaneously enable or disable all eight outputs. This configuration is electrically valid and commonly used to simplify PCB routing. However, doing so eliminates independent control of the two 4-bit groups - a capability retained when using separate enables. The 74FCT244ATPYG's input structure supports this tie without additional loading or timing penalty.

Is the 74FCT244ATPYG pin-compatible with the 74FCT244TPYG?

No, the 74FCT244ATPYG is not pin-compatible with the 74FCT244TPYG. While both use TSSOP-20 packages, the "T" version has different AC characteristics (slower tPLH/tPHL = 4.8 ns max) and lacks the "A" grade's tighter propagation delay (4.1 ns max) and improved drive consistency. Pinout is identical, but electrical behavior differs - substitution requires validation of timing margins in the target design. The 74FCT244ATPYG is not a drop-in replacement for the "T" variant in timing-critical applications.

What is the thermal resistance (θJA) for the 74FCT244ATPYG in TSSOP-20 package?

The datasheet for the 74FCT244ATPYG does not publish θJA (junction-to-ambient thermal resistance) for the PYG (TSSOP-20) package. Typical θJA for similar Renesas TSSOP-20 logic devices ranges from 140–160°C/W with standard 1-inch² 2-layer board layout. For thermal design, assume worst-case power dissipation of 3.5 mA × 5 V = 17.5 mW (IC total current at 10 MHz), resulting in <3°C junction rise above ambient - well within safe limits. The 74FCT244ATPYG requires no heatsinking in standard industrial applications.