Texas Instruments CY74FCT245CTSOCTE4

Overview

CY74FCT245CTSOCTE4 from Texas Instruments is an 8-bit noninverting bidirectional transceiver with 3-state outputs, designed for bus-oriented data routing between two 8-bit ports (A and B). It features 64-mA sink / 32-mA source drive strength, 4.1-ns max propagation delay, Ioff partial-power-down support, and TTL-compatible input/output logic levels.

For engineers reviewing the CY74FCT245CTSOCTE4 datasheet, CY74FCT245CTSOCTE4 pinout, CY74FCT245CTSOCTE4 application, or CY74FCT245CTSOCTE4 equivalent, key selection criteria include direction control (T/R), output enable (OE), high-noise-immunity edge-rate control, and SOIC-20 package compatibility with industrial temperature range (–40°C to 85°C).

Technical Context

This device implements dual 8-bit bidirectional data paths controlled by independent T/R (transmit/receive) and OE (output enable) inputs. The T/R signal determines data flow direction (A→B when high, B→A when low), while OE places both A and B ports in high-impedance state when asserted high.

It uses FCT-family silicon with edge-rate control circuitry to reduce switching noise, matched rise/fall times, and Ioff protection that disables outputs and prevents backflow current during power-down. Fully compatible with TTL voltage thresholds, it operates at VCC = 4.75 V to 5.25 V.

Key Specifications

Pinout & Package

Package: SOIC-20 (DW), 7.5 mm × 12.8 mm body, 1.27 mm pitch, 2.65 mm max height, RoHS-compliant NiPdAu lead finish, MSL Level-1 (unlimited floor life).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74FCT245CTSOCT, CY74FCT245CTSOCTE4 offers identical performance and drop-in compatibility; versus 74LCX245MTCX, it provides full 5-V operation, stronger drive, Ioff safety, and proven noise immunity-critical for mixed-voltage industrial and legacy interfaces.

Availability

CY74FCT245CTSOCTE4 is available at Aetrix Electronics and suitable for industrial automation, legacy computing interface, and automotive body control applications requiring stable component supply and long-term lifecycle support.

Supply support for CY74FCT245CTSOCTE4 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 connectivity technologies, with decades of experience in industrial, automotive, and communications ICs.

The CY74FCT245 series belongs to TI's Fast CMOS Technology (FCT) logic family, engineered for high-speed, low-noise, 5-V bus interface applications in mission-critical industrial and legacy system environments.

FAQ

What is the maximum operating frequency supported by CY74FCT245CTSOCTE4?

CY74FCT245CTSOCTE4 does not specify a maximum clock frequency, as it is a combinatorial transceiver-not a clocked device. Its 4.1-ns max propagation delay enables reliable use in systems with bus toggle rates up to ~200 MHz (based on 5× delay margin rule), provided setup/hold timing at connected devices is met. Actual usable frequency depends on load capacitance, trace routing, and driver strength of upstream components.

Does CY74FCT245CTSOCTE4 support hot-swap or live-insertion?

Yes, CY74FCT245CTSOCTE4 supports partial-power-down via its Ioff feature: when VCC = 0 V, leakage current is limited to ±1 µA even with valid input signals present. This prevents damaging current backflow during hot-swap events in modular backplanes or field-replaceable units-making CY74FCT245CTSOCTE4 suitable for systems requiring live insertion without auxiliary power sequencing.

Can CY74FCT245CTSOCTE4 interface directly with 3.3-V microcontrollers?

CY74FCT245CTSOCTE4 accepts 3.3-V logic HIGH inputs (VIH = 2.0 V min), so it can safely receive signals from 3.3-V MCUs. However, its outputs swing to ~3.3 V (VOH typ) at 32-mA source, which may fall below minimum VIH of some 3.3-V receivers. For guaranteed compatibility, use external pull-ups or verify receiver VIH spec; for robust 3.3-V interfacing, consider a dedicated 3.3-V transceiver like SN74LVC245A.

What is the purpose of the T/R and OE pins on CY74FCT245CTSOCTE4?

The T/R (transmit/receive) pin controls data direction: high enables A→B flow, low enables B→A flow. The OE (output enable) pin, when high, forces both A and B ports into high-impedance state-disabling the device electrically from the bus. These two independent controls allow CY74FCT245CTSOCTE4 to manage bidirectional data routing and bus arbitration in shared-resource systems without external logic.

Is CY74FCT245CTSOCTE4 pin-compatible with older 74F245 or 74LS245 devices?

CY74FCT245CTSOCTE4 shares the same SOIC-20 pinout and function table as industry-standard 74F245 and 74LS245, including identical A/B port mapping, T/R, OE, VCC, and GND locations. However, it is not a direct replacement due to higher drive strength (64/32 mA vs. 20/0.4 mA), faster timing, and different DC characteristics-designers must verify timing margins, bus loading, and power delivery before substitution.