Texas Instruments CY74FCT163H952CPVC

Overview

CY74FCT163H952 from Texas Instruments is a 16-bit registered transceiver with bus-hold inputs, designed for high-speed bidirectional data flow between two 16-bit buses in industrial systems. It features 24 mA balanced drive outputs, 4.4 ns propagation delay (FCT-C speed), 2.7V–3.6V VCC operation, and operates across –40°C to +85°C. It enables reliable A-to-B and B-to-A registered data transfer in backplane and memory interface applications.

For engineers reviewing the CY74FCT163H952 datasheet, CY74FCT163H952 pinout, CY74FCT163H952 application, or CY74FCT163H952 equivalent, key selection criteria include bus-hold functionality eliminating external pull resistors, 5V-tolerant I/O for mixed-voltage interfacing, power-off disable for live insertion, edge-rate control for noise reduction, and industrial temperature compliance.

Technical Context

The CY74FCT163H952 implements dual 8-bit registered transceivers internally synchronized by separate A-to-B and B-to-A clock paths (CLKAB/CLKBA), each controlled by dedicated clock-enable (CEAB/CEBA) and output-enable (OEAB/OEBA) signals. Data latching occurs on LOW-to-HIGH clock transitions when the corresponding CE is active LOW.

Its bus-hold circuitry actively retains the last logic state on all data inputs (A and B ports) when driven sources go high-impedance, eliminating floating inputs without external biasing. Outputs feature current-limiting resistors and 24 mA balanced drive, reducing ground bounce and undershoot while minimizing need for external termination.

Key Specifications

Pinout & Package

Package: 56-pin SSOP (O56), 300-mil body width, JEDEC MO-118 compliant, 0.025-inch pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY74FCT163952CPVC, the CY74FCT163H952CPVC adds bus-hold for floating-input resilience but increases input leakage; versus SN74ALVCH162245DGGR, it provides 5 V tolerance and hot-swap support at the cost of higher quiescent current and larger package footprint.

Availability

CY74FCT163H952 is available at Aetrix Electronics and suitable for industrial backplane routing, modular I/O expansion, and mixed-voltage memory interfacing requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for CY74FCT163H952 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 company delivering analog and embedded processing solutions for industrial, automotive, and communications markets.

The CY74FCT163H952 belongs to TI's FCT logic family, engineered for high-speed, low-noise registered data transfer in industrial control and telecom infrastructure where reliability, voltage translation, and hot-swap capability are essential.

FAQ

What is the primary function of the CY74FCT163H952 in a system design?

The CY74FCT163H952 serves as a 16-bit registered bidirectional transceiver that synchronizes and isolates data flow between two buses using independent A-to-B and B-to-A clock and control paths. Its bus-hold inputs prevent floating states, and its 5 V-tolerant I/O enables interoperability between 3.3 V logic and legacy 5 V peripherals. The CY74FCT163H952 is commonly deployed in backplane interfaces, modular I/O systems, and memory expansion subsystems where deterministic timing and robust signal integrity are required.

Does the CY74FCT163H952 support live insertion, and how is this implemented?

Yes, the CY74FCT163H952 supports live insertion through its power-off disable feature: when VCC drops to 0 V, outputs automatically enter high-impedance mode with IOFF ≤ ±100 µA, preventing back-driving of powered system buses. This behavior is intrinsic to the device's output structure and requires no external circuitry. The CY74FCT163H952 leverages this capability in modular chassis applications where boards are inserted or removed without powering down the entire system.

How does bus-hold functionality affect the design of systems using the CY74FCT163H952?

Bus-hold on the CY74FCT163H952 actively retains the last valid logic state on all A and B port inputs when external drivers are disconnected or tri-stated, eliminating the need for discrete pull-up or pull-down resistors. This reduces component count, PCB area, and potential noise coupling from resistor networks. However, bus-hold current (±50 µA) is higher than standard CMOS inputs (±1 µA), so designers must verify compatibility with weak-drive sources and avoid using the CY74FCT163H952 for rail-to-rail CMOS-to-3.3 V translation per manufacturer guidance.

What are the key timing parameters that define the synchronous operation of the CY74FCT163H952?

The CY74FCT163H952 specifies tPLH/tPHL ≤ 4.4 ns (VCC = 3.0–3.6 V), tSU ≥ 2.5 ns (data to CLK), tH ≥ 1.5 ns (data hold to CLK), and tW ≥ 3.0 ns (minimum clock pulse width). These values ensure reliable registration of data on LOW-to-HIGH clock transitions when CE is asserted. Output enable/disable times (tPZH/tPLZ ≤ 5.2 ns) allow fast direction switching. All timing is guaranteed over –40°C to +85°C, making the CY74FCT163H952 suitable for deterministic real-time control loops.

Can the CY74FCT163H952 be used in mixed-voltage systems, and what are the voltage interface limits?

Yes, the CY74FCT163H952 is explicitly designed for mixed-voltage operation: inputs tolerate –0.5 V to +7.0 V regardless of VCC, enabling direct connection to 5 V TTL/CMOS drivers while powered from 2.7–3.6 V. Outputs swing rail-to-rail within the VCC range and drive 24 mA, supporting 3.3 V logic levels with margin. However, the CY74FCT163H952 is not recommended for translating full-rail 5 V CMOS signals to 3.3 V due to bus-hold interaction - use only with properly terminated or current-limited 5 V sources.