Texas Instruments SN74CBTD3384CPWRE4

Overview

SN74CBTD3384CPWRE4 from Texas Instruments is a 10-bit TTL-compatible FET bus switch with dual 5-bit sections, 3 Ω typical ON-state resistance, −2 V undershoot protection on A/B ports, and integrated VCC-level-shifting diode enabling 5-V-to-3.3-V bidirectional signal translation. It supports memory interleaving and bus isolation in mixed-voltage systems.

For engineers reviewing the SN74CBTD3384CPWRE4 datasheet, SN74CBTD3384CPWRE4 pinout, SN74CBTD3384CPWRE4 application, or SN74CBTD3384CPWRE4 equivalent, key selection criteria include its Ioff partial-power-down capability, 0.15 ns propagation delay, 5 pF OFF-state I/O capacitance, and TSSOP-24 package compatibility with high-density PCB layouts.

Technical Context

The SN74CBTD3384CPWRE4 implements two independent 5-bit FET bus switches controlled by separate OE inputs (1OE, 2OE), enabling configurable 5-bit or consolidated 10-bit operation. Each switch provides true bidirectional conduction with near-zero propagation delay due to low ron and minimal parasitic capacitance.

Its active undershoot-protection circuitry monitors A/B port voltages and forces OFF-state isolation during −2 V transients, while the integrated series diode between VCC and input enables deterministic 5-V-to-3.3-V level shifting without external components. Ioff functionality guarantees isolation when VCC = 0 V, preventing backdrive current in partial-power-down systems.

Key Specifications

Pinout & Package

TSSOP-24 package (PW), 7.9 mm × 4.5 mm body, 1.2 mm max height, 0.65 mm pitch, exposed pad not present, JEDEC MO-153 compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBTD3384CPWRE4, SN74CBT3384CPWR omits level-shifting and undershoot protection but offers lower unit cost, while SN74LVC1G3157DCKR trades bus-width scalability for wider VCC flexibility and smaller footprint-neither matches the combined 10-bit bidirectional level-shifting and transient-hardened functionality of the SN74CBTD3384CPWRE4.

Availability

SN74CBTD3384CPWRE4 is available at Aetrix Electronics and suitable for memory subsystems, industrial bus interfaces, FPGA configuration links, and mixed-voltage embedded controllers requiring stable component supply and long-term production continuity.

Supply support for SN74CBTD3384CPWRE4 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 with over 50 years of innovation in high-reliability interface and signal-path components.

The SN74CBTD3384CPWRE4 belongs to TI's CBTD family of high-speed FET bus switches, engineered specifically for low-latency, low-distortion, mixed-voltage digital interconnect in memory, computing, and industrial control systems.

FAQ

What is the primary function of the SN74CBTD3384CPWRE4?

The SN74CBTD3384CPWRE4 is a 10-bit bidirectional FET bus switch with dual 5-bit sections, designed to provide low-latency, low-distortion signal routing between mixed-voltage domains. Its core functions include 5-V-to-3.3-V level shifting via an integrated VCC-diode, −2 V undershoot protection on all I/O ports, and Ioff-enabled partial-power-down isolation. The SN74CBTD3384CPWRE4 operates with 0.15 ns propagation delay and 3 Ω typical ON-resistance, making it ideal for memory interleaving and high-speed bus gating.

Does the SN74CBTD3384CPWRE4 support true bidirectional operation?

Yes, the SN74CBTD3384CPWRE4 supports true bidirectional data flow between its A and B ports without direction-control pins. When an output-enable input (1OE or 2OE) is low, the corresponding 5-bit switch connects A and B ports with near-zero resistance and symmetric electrical characteristics in both directions. This behavior is confirmed by its ron specification (3 Ω typical), matched Cio(ON) (12.5 pF), and absence of directional asymmetry in switching timing parameters. The SN74CBTD3384CPWRE4 maintains this bidirectionality across its full 0–5.5 V I/O voltage range.

How does the undershoot protection work on the SN74CBTD3384CPWRE4?

The SN74CBTD3384CPWRE4 features dedicated active undershoot-protection circuitry on both A and B ports that detects voltage excursions below −2 V and forces the associated FET switch into a guaranteed OFF state-even if the output-enable signal is asserted. This prevents false conduction and potential latch-up during negative transients caused by transmission-line reflections or ESD events. The protection is independent of VCC status and remains functional down to VCC = 0 V, ensuring robustness during power-up/down sequences. The SN74CBTD3384CPWRE4 datasheet specifies VIKU = −2 V (min) under defined test conditions.

Can the SN74CBTD3384CPWRE4 be used for analog signal switching?

Yes, the SN74CBTD3384CPWRE4 is qualified for analog signal switching applications due to its low ON-state resistance (3 Ω typical), low OFF-state capacitance (5 pF), and flat ron vs. voltage profile across its 0–5.5 V I/O range. Its bidirectional nature, absence of body diodes in the signal path, and rail-to-rail voltage handling enable distortion-free transmission of DC-coupled analog signals up to ~100 MHz bandwidth. However, it is not specified for precision analog performance (e.g., THD, leakage), so the SN74CBTD3384CPWRE4 is best suited for general-purpose analog gating-not high-fidelity audio or instrumentation-grade paths.

What is the recommended power-up sequence for the SN74CBTD3384CPWRE4?

To ensure predictable high-impedance behavior during power-up, TI recommends tying both 1OE and 2OE to VCC through pullup resistors. The minimum resistor value depends on the driver's current-sinking capability but must guarantee OE remains above VIH (2 V min) until VCC stabilizes within 4.5–5.5 V. This prevents momentary undefined states that could cause bus contention. The SN74CBTD3384CPWRE4 does not require strict VCC-first sequencing due to its Ioff and undershoot protection, but OE control stability remains critical. Always verify OE logic levels relative to the final VCC value before enabling data flow.