Texas Instruments SN74CBTD3384PWRE4

Overview

SN74CBTD3384PWRE4 from Texas Instruments is a 10-bit high-speed TTL-compatible bus switch IC with dual 5-bit independent channels, 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 systems.

For engineers reviewing the SN74CBTD3384PWRE4 datasheet, SN74CBTD3384PWRE4 pinout, SN74CBTD3384PWRE4 application, or SN74CBTD3384PWRE4 equivalent, this device supports fast bidirectional switching in memory interface, FPGA I/O expansion, and voltage-domain bridging where low-insertion-loss, rail-to-rail signal integrity, and OE-controlled isolation are critical.

Technical Context

The SN74CBTD3384PWRE4 implements two independent 5-bit analog bus switches controlled by separate active-low output-enable (1OE, 2OE) inputs; each channel connects port A to port B when its OE is low and presents high-impedance isolation when OE is high. Its low on-resistance (5 Ω typical) minimizes RC delay and maintains signal edge fidelity at high frequencies.

Integrated diodes to VCC enable level shifting from 5-V inputs to 3.3-V outputs without external components. The device operates over 4.5–5.5 V supply range and supports −40°C to 85°C ambient temperature, with input clamp current rated to ±50 mA and continuous channel current up to 128 mA.

Key Specifications

Pinout & Package

TSSOP-24 package (PW), 7.8 mm × 4.4 mm footprint, 1.2 mm maximum height, lead pitch 0.65 mm, RoHS-compliant NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBTD3384PWRE4, SN74CBT3384PWRE4 offers identical packaging and control but omits level-shifting capability, while SN74LVC1G3157DCKR trades bus-width and dual-OE flexibility for ultra-small SC70-6 footprint and single-channel precision-making each viable only in narrowly defined subsystem roles.

Availability

SN74CBTD3384PWRE4 is available at Aetrix Electronics and suitable for memory interface bridging, FPGA I/O expansion, PCI/ISA bus isolation, and industrial control backplane applications requiring stable component supply and long-term industrial temperature support.

Supply support for SN74CBTD3384PWRE4 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-reliability logic and interface solutions.

The 'CBTD3384 product line was designed specifically for high-speed, low-latency bidirectional bus switching in mixed-voltage digital systems-targeting memory subsystems, programmable logic interconnects, and industrial backplanes.

FAQ

What is the maximum continuous current rating per channel for SN74CBTD3384PWRE4?

The SN74CBTD3384PWRE4 supports a continuous channel current of 128 mA per switched path, verified under recommended operating conditions (VCC = 4.5 V to 5.5 V, TA = −40°C to +85°C). This rating applies to any individual A–B connection (e.g., 1A1 ↔ 1B1) and is not shared across channels. Exceeding this value risks thermal overstress or parametric shift.

Does SN74CBTD3384PWRE4 support true bidirectional signal flow?

Yes, SN74CBTD3384PWRE4 is fully bidirectional: signals pass equally well from port A to port B or port B to port A when the corresponding OE is low. Its analog switch architecture imposes no directionality-unlike digital transceivers-and preserves signal polarity, slew rate, and DC characteristics in both directions.

Can SN74CBTD3384PWRE4 be used for 3.3-V-to-5-V level shifting?

No, SN74CBTD3384PWRE4 integrates diodes from inputs to VCC to enable 5-V-to-3.3-V translation only. Driving 3.3-V signals into the A or B ports while VCC = 5 V does not produce a boosted 5-V output; the device lacks active pull-up or charge-pump circuitry required for upward translation.

What is the thermal resistance (θJA) of the TSSOP-24 (PW) package for SN74CBTD3384PWRE4?

The published junction-to-ambient thermal resistance (θJA) for SN74CBTD3384PWRE4 in the PW package is 88°C/W, measured per JESD 51-7 under standard JEDEC high-K board conditions. This value assumes a 2-layer PCB with 1-in² copper pour under the exposed pad; actual performance improves with enhanced thermal vias and multilayer layout.

Are unused OE inputs required to be tied high or low for proper operation of SN74CBTD3384PWRE4?

Yes-per TI Application Report SCBA004, all unused control inputs (including 1OE and 2OE) must be held statically at either VCC or GND. Floating OE pins cause undefined switch states, increased ICC, and potential oscillation due to slow input transitions; tying to VCC disables the associated channel, while tying to GND enables it.