Texas Instruments CY74FCT2245TSOCTG4

Overview

CY74FCT2245TSOCTG4 from Texas Instruments is an 8-bit noninverting bidirectional transceiver with 3-state outputs, designed for bus interface applications. It features 12 mA sink / 15 mA source drive strength, 25-Ω integrated output series resistors, Ioff partial-power-down support, and TTL-compatible logic levels. It operates across –40°C to 85°C in a 20-pin SOIC package and replaces CY74FCT245T in noise-sensitive backplane or data-bus designs.

For engineers reviewing the CY74FCT2245TSOCTG4 datasheet, CY74FCT2245TSOCTG4 pinout, CY74FCT2245TSOCTG4 application, or CY74FCT2245TSOCTG4 equivalent, key selection criteria include direction control (T/R), 3-state enable (OE), bus noise suppression via on-die termination, Ioff protection during power sequencing, and compatibility with legacy FCT/F logic families.

Technical Context

The CY74FCT2245TSOCTG4 implements dual-port bidirectional data flow controlled by active-high T/R and active-high OE signals: T/R = high enables A→B transfer; T/R = low enables B→A transfer; OE = high forces both ports into high-impedance state. Its edge-rate control circuitry limits slew rate to reduce EMI and transmission-line reflections.

It integrates 25-Ω series output resistors per channel to dampen ringing without external components, supports Ioff (≤±1 µA at VCC = 0 V) for live-insertion and hot-swap systems, and maintains full TTL input/output voltage compatibility (VIH = 2 V min, VOL = 0.55 V max at 12 mA).

Key Specifications

Pinout & Package

20-pin SOIC (DW) package, 7.5 mm × 12.8 mm body, 1.27 mm pitch, 2.65 mm max height, RoHS-compliant NiPdAu lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74FCT245ATSOCT and 74LVC245APW,215, the CY74FCT2245TSOCTG4 uniquely combines 5-V TTL compatibility, on-die termination, and Ioff in a single SOIC-20 package-making it the only option that eliminates external resistors while supporting hot-swap and mixed-voltage bus isolation without redesign.

Availability

CY74FCT2245TSOCTG4 is available at Aetrix Electronics and suitable for industrial automation, legacy system upgrades, and embedded memory expansion requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant sourcing.

Supply support for CY74FCT2245TSOCTG4 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 delivering analog, embedded processing, and connectivity solutions with emphasis on reliability, longevity, and industrial-grade performance.

The CY74FCT2245TSOCTG4 belongs to TI's FCT logic family, engineered specifically for noise-immune, high-speed digital bus interfacing in industrial, telecom, and computing infrastructure where signal integrity and power sequencing robustness are critical.

FAQ

What is the maximum operating frequency supported by the CY74FCT2245TSOCTG4?

The CY74FCT2245TSOCTG4 has a maximum propagation delay of 7 ns (tPLH/tPHL) under load (CL = 50 pF), enabling reliable operation up to approximately 143 MHz in point-to-point bus configurations. Actual achievable frequency depends on trace length, termination, and fanout; for 10–15 cm PCB traces with proper grounding, 50–80 MHz is typical in production systems using the CY74FCT2245TSOCTG4.

Does the CY74FCT2245TSOCTG4 require external pull-up or pull-down resistors on T/R or OE inputs?

No - the CY74FCT2245TSOCTG4 does not require external biasing on T/R or OE. Its inputs have CMOS-compatible thresholds and leakage < ±1 µA, so they must be actively driven to valid logic levels (VCC or GND) per TI's recommended operating conditions. Floating inputs are prohibited and may cause undefined output states or increased ICC.

Can the CY74FCT2245TSOCTG4 be used in mixed-voltage systems, such as interfacing a 3.3-V MCU with a 5-V peripheral?

No - the CY74FCT2245TSOCTG4 is a 5-V-only device (VCC = 4.75–5.25 V) with TTL-compatible input thresholds (VIH ≥ 2 V). While it can accept 3.3-V logic HIGH from a properly designed MCU (if VOH ≥ 2.4 V), its outputs swing 0.55 V/2.4 V and are not 3.3-V tolerant. Direct connection to 3.3-V-only inputs risks overvoltage damage; level translation is required for safe 3.3-V ↔ 5-V interfacing using the CY74FCT2245TSOCTG4.

How does the 25-Ω output series resistor in the CY74FCT2245TSOCTG4 improve signal integrity?

The integrated 25-Ω series resistor in the CY74FCT2245TSOCTG4 forms a source-termination network with typical PCB trace impedance (~50 Ω), reducing signal reflections at the load end. This minimizes overshoot, undershoot, and ringing - especially on traces >5 cm - eliminating need for discrete 25-Ω resistors per line and improving timing margin without layout changes. Measured Rout = 20–40 Ω confirms design consistency across process/voltage/temperature for the CY74FCT2245TSOCTG4.

Is the CY74FCT2245TSOCTG4 pin-compatible with the CY74FCT245T series?

Yes - the CY74FCT2245TSOCTG4 is functionally and physically pin-compatible with CY74FCT245T variants in the same SOIC-20 package. Both share identical pinout (T/R, A0–A7, GND, VCC, OE, B0–B7), logic behavior, and timing specs. The CY74FCT2245TSOCTG4 adds on-die 25-Ω termination and enhanced edge-rate control, making it a direct drop-in upgrade for noise reduction without PCB modification.