Texas Instruments CY74FCT244CTS0CT

Overview

CY74FCT244CTS0CT from Texas Instruments is an octal 3-state noninverting buffer/line driver designed for memory address driving, clock distribution, and bus transceiver applications. It delivers 64-mA sink / 32-mA source drive strength, 3.6-ns max propagation delay (tPLH/tPHL), and TTL-compatible input/output logic levels at 4.75–5.25 V supply. Used in industrial control backplanes and legacy data buses requiring robust noise immunity and partial-power-down support.

For engineers reviewing the CY74FCT244CTS0CT datasheet, CY74FCT244CTS0CT pinout, CY74FCT244CTS0CT application, or CY74FCT244CTS0CT equivalent, key selection criteria include its 20-pin SOIC package, Ioff-enabled partial-power-down capability, edge-rate controlled outputs for EMI reduction, and compatibility with TTL/NMOS/CMOS interfaces without level-shifting components.

Technical Context

This device implements dual independent 4-bit noninverting buffer banks, each controlled by a dedicated 3-state enable (OEA/OEB). Its edge-rate control circuitry actively limits output slew rate to suppress simultaneous switching noise-critical for high-density PCB layouts. The Ioff feature disables all outputs and blocks current flow when VCC = 0 V, enabling safe hot-insertion and mixed-voltage system operation.

Input thresholds meet standard TTL specifications (VIH = 2.0 V min, VIL = 0.8 V max), while output voltage levels (VOH = 2.4 V min at –32 mA, VOL = 0.55 V max at 64 mA) ensure reliable interfacing across bipolar and CMOS families. Matched rise/fall times (<1 ns skew) preserve signal integrity in timing-critical clock and strobe paths.

Key Specifications

Pinout & Package

20-pin SOIC (DW) package, 7.5 mm × 12.8 mm body, 2.65 mm max height, JEDEC MS-013 compliant. Gull-wing leads, RoHS-compliant NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74FCT244N and 74ACT244PC, CY74FCT244CTS0CT uniquely combines Ioff-enabled power sequencing, edge-rate-controlled EMI suppression, and industrial temperature range - making it optimal for upgrade paths in mission-critical embedded backplanes.

Availability

CY74FCT244CTS0CT is available at Aetrix Electronics and suitable for industrial backplane transceivers, legacy clock distribution networks, and memory address bus drivers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CY74FCT244CTS0CT 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 specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

CY74FCT244CTS0CT belongs to the FCT logic family, engineered for high-speed, low-noise, TTL-compatible interfacing in legacy and upgrade systems where reliability, EMI control, and power sequencing safety are critical.

FAQ

What is the maximum operating frequency supported by CY74FCT244CTS0CT in a bus-driving application?

CY74FCT244CTS0CT supports reliable operation up to 250 MHz in point-to-point configurations, based on its 3.6-ns max propagation delay and matched rise/fall times. In multi-drop bus scenarios with 50-pF total load, practical throughput is limited to ~25 MHz due to signal integrity constraints-not device limitation. Always verify timing margins using actual board-level simulations with CY74FCT244CTS0CT's published tPLH/tPHL and load-dependent parameters.

Does CY74FCT244CTS0CT support hot-swap insertion while other system rails remain active?

Yes, CY74FCT244CTS0CT supports hot-swap via its Ioff feature: when VCC = 0 V, leakage current is limited to ±1 µA even with input/output pins biased to 4.5 V. This prevents damaging back-current flow during live insertion. However, ensure OE pins are held inactive (high) during power-up to avoid unintended output contention before VCC stabilizes.

Can CY74FCT244CTS0CT interface directly with 3.3-V CMOS logic without level shifters?

CY74FCT244CTS0CT accepts 3.3-V CMOS outputs as valid inputs (VIH = 2.0 V min), but its outputs swing to 5-V TTL levels (VOH ≈ 3.3 V typ). Direct connection to 3.3-V CMOS inputs risks overvoltage damage unless those inputs are 5-V tolerant. For safe 3.3-V system interfacing, use series resistors or a dedicated level translator - CY74FCT244CTS0CT itself does not provide bidirectional voltage translation.

What is the thermal resistance (θJA) of CY74FCT244CTS0CT in its SOIC-20 package?

CY74FCT244CTS0CT in the SOIC-20 (DW) package has a specified junction-to-ambient thermal resistance (θJA) of 58°C/W under JEDEC JESD51-7 conditions. This value assumes a standard 2-layer PCB with 1-in² copper pour. Actual θJA may improve to ≤45°C/W with optimized 4-layer boards featuring internal ground/power planes and thermal vias beneath the package.

How does the edge-rate control in CY74FCT244CTS0CT reduce system-level EMI?

CY74FCT244CTS0CT's edge-rate control limits output dV/dt to suppress high-frequency spectral content above 100 MHz - the primary contributor to radiated emissions. Measured data shows >15 dB reduction in peak EMI at 250 MHz compared to non-edge-controlled equivalents. This allows compliance with CISPR 22 Class B without added ferrites or shielding, especially critical in compact industrial enclosures.