Texas Instruments CYBUS3384SOCT

Overview

CYBUS3384SOCT from Texas Instruments is a dual 5-bit bidirectional bus switch IC designed for high-speed, low-noise interconnection between 3.3V and 5.0V logic domains. It features zero propagation delay, 2Ω on-resistance, >500 MΩ off-isolation, and independent BE1/BE2 enables for two 5-bit channels. It is used in VME backplanes, dual-port RAM arbitration, and level-shifting I/O isolation.

For engineers reviewing the CYBUS3384SOCT datasheet, CYBUS3384SOCT pinout, CYBUS3384SOCT application, or CYBUS3384SOCT equivalent, key selection criteria include bidirectional 3.3V/5V translation capability, sub-1ns switching delay, power-off disable functionality, and SOIC-24 package compatibility with legacy board layouts.

Technical Context

The CYBUS3384SOCT implements ten independent N-channel MOSFET switches grouped into two 5-bit banks (A0–A4/B0–B4 and A5–A9/B5–B9), each controlled by dedicated TTL-compatible enable inputs (BE1 and BE2). Its symmetric structure enables true bidirectional signal flow without direction pins or internal buffering.

It operates with VCC = 4.0V to 5.5V, supports direct interface with 5V CMOS/TTL and 3.3V CMOS, and achieves –66 dB crosstalk at 50 MHz. The power-off disable feature eliminates back-powering and ensures high-impedance isolation when VCC = 0V.

Key Specifications

Pinout & Package

Package: 24-pin molded SOIC (S13, 300-mil width), JEDEC MS-013AC compliant, RoHS-compliant lead finish (Pb-Free, per TI eco plan).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3384DBR and 74LVC1G3157DRYR, the CYBUS3384SOCT uniquely supports 4.0V minimum VCC for flexible 3.3V/5V translation and provides independent dual-bank enables-critical for memory arbitration and modular backplane designs where partial bus isolation is required.

Availability

CYBUS3384SOCT is available at Aetrix Electronics and suitable for VMEbus interconnect, dual-port SRAM arbitration, and hot-swap I/O module isolation requiring stable component supply across extended product lifecycles.

Supply support for CYBUS3384SOCT 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.

The CYBUS3384SOCT belongs to TI's legacy CBT (Crossbar Bus Technology) logic family, engineered for ultra-low-latency, high-fidelity digital signal routing in backplane, memory, and modular system architectures.

FAQ

What is the maximum operating frequency supported by the CYBUS3384SOCT?

The CYBUS3384SOCT does not specify a maximum operating frequency because it introduces no active timing elements or propagation delay beyond RC effects. Its usable bandwidth is determined by external load capacitance and source drive strength. Measured crosstalk of –66 dB at 50 MHz confirms suitability for high-speed digital buses up to that frequency, and its 2Ω RON supports clean signal edges into typical 50 Ω–100 Ω loads. The CYBUS3384SOCT remains functional well beyond 50 MHz in low-capacitance point-to-point links.

Can the CYBUS3384SOCT be used for analog signal switching?

Yes, the CYBUS3384SOCT is suitable for small-signal analog applications where crosstalk and off-isolation are critical. Its –66 dB crosstalk at 50 MHz and >500 MΩ off-state resistance meet requirements for audio routing, sensor multiplexing, and test instrumentation. However, it is not specified for rail-to-rail analog swing or precision linearity; input signals must remain within 0 V to VCC – V_TH to avoid MOSFET cutoff. The CYBUS3384SOCT performs best with logic-level or low-voltage analog signals (<3.3 V peak-to-peak).

Does the CYBUS3384SOCT require external pull-up or pull-down resistors on BE1 and BE2?

No, the CYBUS3384SOCT BE1 and BE2 inputs have built-in hysteresis (0.2 V) and TTL-compatible thresholds (V_IL = 0.8 V, V_IH = 2.0 V), allowing direct connection to standard logic outputs without external biasing. Unused BE inputs should be tied to VCC or GND per datasheet guidelines to prevent floating states. The CYBUS3384SOCT internal design ensures reliable enable/disable behavior without external resistors under normal operating conditions.

How does the CYBUS3384SOCT achieve 3.3V-to-5V bidirectional level translation?

The CYBUS3384SOCT achieves bidirectional level translation by operating with a reduced VCC (e.g., 4.3 V via series diode + resistor), which limits the maximum output voltage on the 5V side to ~3.3 V while allowing 3.3 V inputs to fully turn on the N-channel switches. Since the device is passive and symmetric, signals pass in either direction without direction control. The CYBUS3384SOCT leverages its low-threshold N-MOS structure and controlled VCC to enforce voltage clamping inherently-no external translators or direction pins are needed.

Is the CYBUS3384SOCT pin-compatible with other members of the CYBUS3384 family?

Yes, the CYBUS3384SOCT shares identical pinout and functionality with CYBUS3384QC, CYBUS3384QCT, and CYBUS3384SOC - all are 24-pin devices with identical A/B/BE1/BE2/VCC/GND assignments and electrical specifications. The only differences are package type (SOIC vs. QSOP) and marking. Board designs using CYBUS3384SOCT can accept any CYBUS3384 variant without layout changes, though thermal and high-frequency performance may vary slightly due to package parasitics.