Texas Instruments SN74CBTD3384PW

Overview

SN74CBTD3384PW from Texas Instruments is a 10-bit high-speed TTL-compatible bus switch IC with dual 5-bit independent switching banks, 5-Ω on-state resistance, 0.25 ns propagation delay, and integrated level-shifting diode enabling 5-V-to-3.3-V signal translation in mixed-voltage memory and data bus interfaces.

For engineers reviewing the SN74CBTD3384PW datasheet, SN74CBTD3384PW pinout, SN74CBTD3384PW application, or SN74CBTD3384PW equivalent, key selection criteria include bidirectional low-R_ON switching, separate OE control per bank, TTL-compatible input thresholds, and TSSOP-24 package compatibility with high-density PCB layouts.

Technical Context

The SN74CBTD3384PW implements two independent 5-bit bidirectional analog switches controlled by dedicated 1OE and 2OE inputs; each switch connects port A to port B when its OE is low (active-low), presenting high-impedance isolation when OE is high. Its internal V_CC-clamp diode enables level shifting without external components.

Switch operation is voltage-transparent: signals pass unaltered in either direction with no logic inversion or buffering. The device operates across 4.5 V–5.5 V supply range, supports ±128 mA continuous channel current, and maintains sub-nanosecond timing performance under 50 pF load conditions.

Key Specifications

Pinout & Package

TSSOP-24 (PW) package: 0.65 mm pitch, 7.8 mm × 4.4 mm body, 1.2 mm max height, exposed pad not present, JEDEC MO-153 compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3384PW and SN74LVC1G3157DBVR, the SN74CBTD3384PW uniquely combines dual 5-bit banks, 5-Ω R_ON, integrated level shifting, and TTL-compatible control - making it the only direct solution for high-speed mixed-voltage parallel bus isolation without design compromise.

Availability

SN74CBTD3384PW is available at Aetrix Electronics and suitable for memory interface isolation, microcontroller peripheral multiplexing, FPGA I/O translation, and automated test equipment signal routing requiring stable component supply and long-term obsolescence management.

Supply support for SN74CBTD3384PW 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 expertise in high-performance logic and interface solutions.

The 'CBTD3384 family was designed specifically for high-speed, low-latency bus switching in mixed-voltage computing and communications systems where signal integrity, timing predictability, and voltage domain bridging are critical.

FAQ

What is the maximum operating temperature range for the SN74CBTD3384PW?

The SN74CBTD3384PW is rated for operation from −40°C to +85°C ambient temperature. This commercial-grade specification aligns with standard industrial environments and matches the thermal performance validated in TI's recommended operating conditions table. The PW package exhibits 88°C/W junction-to-ambient thermal resistance, requiring appropriate PCB copper area for sustained 128 mA channel current operation within this range. SN74CBTD3384PW must not be operated outside these limits to ensure parametric compliance and reliability.

Does the SN74CBTD3384PW support true bidirectional signal flow?

Yes, the SN74CBTD3384PW provides fully bidirectional analog switching: signals pass identically from port A to port B or port B to port A with no polarity inversion, logic interpretation, or direction control required. Each switch channel behaves as a low-resistance metal path (5 Ω typical) when enabled, preserving waveform shape, DC level, and timing symmetry - essential for protocols like JTAG, SPI, and parallel memory interfaces where direction reversal occurs dynamically. SN74CBTD3384PW achieves this without internal latches or buffers.

Can the SN74CBTD3384PW be used for level shifting between 3.3-V and 5-V logic domains?

Yes, the SN74CBTD3384PW integrates a diode-connected transistor to V_CC on each I/O terminal, enabling automatic 5-V-to-3.3-V level shifting when V_CC = 5 V. Input signals up to 5 V are clamped and translated to ~3.3 V at the opposite port, satisfying 3.3-V logic thresholds. However, 3.3-V-to-5-V translation is not supported - the device does not boost voltages. SN74CBTD3384PW is optimized for downward translation only, as confirmed in TI's functional description and level-shifting application notes.

What is the function of the OE pins on the SN74CBTD3384PW?

The SN74CBTD3384PW features two independent active-low output-enable pins: 1OE controls Bank 1 (1A1–1A5 ↔ 1B1–1B5), and 2OE controls Bank 2 (2A1–2A5 ↔ 2B1–2B5). When an OE pin is low, its corresponding 5-bit switch bank conducts; when high, that bank presents high-impedance isolation between ports. This allows granular bus segmentation - for example, isolating memory address lines while passing data - without affecting the other bank. SN74CBTD3384PW requires OE to be driven to valid TTL logic levels (≤0.8 V for low, ≥2 V for high).

Is the SN74CBTD3384PW pin-compatible with other packages in the CBTD3384 family?

Yes, the SN74CBTD3384PW shares identical pin numbering and signal mapping with the DB, DBQ, DGV, and DW package variants of the CBTD3384 family, as confirmed by TI's top-view diagrams and ordering information tables. All 24-pin versions use the same pinout: 1OE, 1B1–1B5, 1A1–1A5, GND, VCC, 2B5–2B1, 2A5–2A1, 2OE. Mechanical differences (body size, pitch, thermal pad) do not affect electrical connectivity or layout compatibility at the schematic or netlist level. SN74CBTD3384PW may be substituted into existing designs using other 24-pin packages without netlist or footprint changes.