Texas Instruments SN74CBT3384CPWR

Overview

SN74CBT3384CPWR from Texas Instruments is a high-speed TTL-compatible 10-bit FET bus switch organized as two independent 5-bit bidirectional switches, featuring 3 Ω typical ON-state resistance (ron), near-zero propagation delay (0.15 ns at VCC = 5 V), and undershoot protection up to −2 V on A/B ports - used for PCI interface signal gating and memory interleaving in industrial control backplanes.

For engineers reviewing the SN74CBT3384CPWR datasheet, SN74CBT3384CPWR pinout, SN74CBT3384CPWR application, or SN74CBT3384CPWR equivalent, key selection criteria include Ioff partial-power-down support, 0–5-V data I/O level compatibility, 5-pF typical OFF-state input/output capacitance, and TSSOP-24 package thermal performance (θJA = 88°C/W).

Technical Context

The SN74CBT3384CPWR implements dual 5-bit FET-based analog/digital bus switches with separate 1OE and 2OE enable controls. Each switch channel operates bidirectionally with no direction pin, relying on voltage-level transparency between A and B ports when enabled.

Its active undershoot-protection circuitry monitors A/B port voltages and forces the switch into high-impedance state during −2 V transients, while Ioff functionality prevents backflow current during partial power-down - critical for hot-swap and mixed-voltage system designs.

Key Specifications

Pinout & Package

TSSOP-24 package (PW), 7.9 mm × 4.5 mm × 1.2 mm max height, lead pitch 0.65 mm, moisture sensitivity level 1 (unlimited reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3384CPWR, SN74CBTD3384CPWR offers enhanced control-input voltage flexibility but higher quiescent current, while SN74LVC1G3157DCKR trades bus-width capability and protection features for ultra-small footprint - making SN74CBT3384CPWR optimal for 10-bit, high-reliability, mixed-voltage bus isolation.

Availability

SN74CBT3384CPWR is available at Aetrix Electronics and suitable for PCI interface design, memory interleaving architectures, and industrial backplane bus isolation requiring stable component supply across extended temperature ranges (−40°C to 85°C).

Supply support for SN74CBT3384CPWR 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 SN74CBT3384CPWR belongs to TI's CBT (Crossbar Bus Transceiver) logic family, engineered for high-speed, low-distortion digital and analog signal routing in computing, industrial automation, and communications infrastructure.

FAQ

What is the maximum undershoot voltage the SN74CBT3384CPWR can withstand on its A/B ports?

The SN74CBT3384CPWR provides active undershoot protection up to −2 V on both A and B ports, as verified in the absolute maximum ratings and undershoot characteristics sections of the official datasheet. This protection is implemented via internal sensing circuitry that forces the switch into high-impedance state during transient events, preventing unintended conduction. The SN74CBT3384CPWR maintains this rating across its full operating temperature range (−40°C to 85°C) and VCC range (4 V to 5.5 V).

Does the SN74CBT3384CPWR support partial-power-down operation, and how is it implemented?

Yes, the SN74CBT3384CPWR supports partial-power-down operation via its Ioff feature, which limits leakage current to 10 µA when VCC = 0 V and data I/Os are biased between 0 V and 5.5 V. This is achieved through internal transistor biasing that disables current paths between ports during power-off conditions. The SN74CBT3384CPWR meets JESD 78 Class II latch-up immunity (>100 mA), ensuring robustness in hot-swap and modular system designs where power sequencing is non-uniform.

What is the typical ON-state resistance (ron) of the SN74CBT3384CPWR, and under what conditions is it measured?

The SN74CBT3384CPWR has a typical ON-state resistance (ron) of 3 Ω, measured at VCC = 4.5 V with VI = 0 V and IO = 30 mA, or at VCC = 4 V with VI = 2.4 V and IO = −15 mA. This value reflects the voltage drop across the A–B channel under defined load conditions and is confirmed in the electrical characteristics table. The SN74CBT3384CPWR maintains ron ≤ 6 Ω across its full recommended operating range, ensuring predictable signal attenuation in high-speed digital and analog routing applications.

Can the SN74CBT3384CPWR be used with 1.8-V or 2.5-V logic families, and what ensures compatibility?

Yes, the SN74CBT3384CPWR supports 0–5-V signaling levels on its data I/Os, explicitly covering 0.8-V, 1.2-V, 1.5-V, 1.8-V, 2.5-V, 3.3-V, and 5-V logic families. Compatibility is ensured by rail-to-rail input/output voltage tolerance, low 5-pF OFF-state capacitance (minimizing loading), and TTL/CMOS-compatible control inputs (VIH = 2 V min, VIL = 0.8 V max). The SN74CBT3384CPWR requires no external level shifters when interfacing mixed-voltage buses, as confirmed in the "Data I/Os Support 0 to 5-V Signaling Levels" specification.

What package type and thermal characteristics apply to the SN74CBT3384CPWR?

The SN74CBT3384CPWR is packaged in a TSSOP-24 (PW) outline measuring 7.9 mm × 4.5 mm × 1.2 mm max height, with 0.65 mm lead pitch and moisture sensitivity level 1 (unlimited reflow). Its thermal impedance is θJA = 88°C/W under JEDEC-standard PCB conditions, as documented in the absolute maximum ratings table. This package supports high-density surface-mount assembly and is validated for industrial temperature operation (−40°C to 85°C), with NIPDAU lead finish and RoHS compliance confirmed in TI's packaging addendum.