Texas Instruments SN74CBTS3384DBR

Overview

SN74CBTS3384DBR from Texas Instruments is a 10-bit FET bus switch with Schottky diode clamping, designed for high-speed TTL-compatible signal routing in backplane and board-level interconnects. It features 5-Ω on-state resistance, 0.25 ns typical propagation delay at 5 V, and dual independent 5-bit channels controlled by separate OE inputs. Used in hot-swap-capable data paths and level-translating I/O expansion.

For engineers reviewing the SN74CBTS3384DBR datasheet, SN74CBTS3384DBR pinout, SN74CBTS3384DBR application, or SN74CBTS3384DBR equivalent, key selection criteria include on-resistance matching, undershoot clamping capability, dual-channel enable control, and SSOP-24 thermal performance (θ_JA = 61°C/W).

Technical Context

The SN74CBTS3384DBR implements two independent 5-bit FET-based analog switches with bidirectional signal flow and integrated Schottky clamps on all A/B I/O pins to suppress negative undershoot transients. Its TTL-compatible control inputs accept 0.8 V/2.0 V thresholds and drive low-impedance gates without external pull-ups.

Each channel operates as a voltage-controlled transmission gate: when OE is low, the corresponding 5-bit path conducts with minimal RC delay; when OE is high, both ports enter high-impedance isolation. No internal level-shifting or direction control logic is present - operation is strictly analog pass-through with digital enable gating.

Key Specifications

Pinout & Package

SN74CBTS3384DBR uses a 24-pin SSOP (Shrink Small Outline Package) with 0.65 mm lead pitch and 1.2 mm max height. The package provides mechanical robustness and thermal performance suitable for automated SMT assembly and industrial environments.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3384DBR and SN74LVC1G3157DCKR, the SN74CBTS3384DBR uniquely combines dual 5-bit channels, Schottky clamping, and 5-Ω r_ON in a single SSOP-24 package - making it irreplaceable for compact, robust, high-speed bus isolation where undershoot suppression is mandatory.

Availability

SN74CBTS3384DBR is available at Aetrix Electronics and suitable for industrial backplane interconnects, hot-swap I/O expansion modules, and test access multiplexers requiring stable component supply and guaranteed long-term sourcing.

Supply support for SN74CBTS3384DBR 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 over 90 years of innovation in industrial, automotive, and communications markets.

The SN74CBTS3384DBR belongs to TI's CBTS (CMOS Bus Transceiver Switch) family, engineered specifically for high-speed, low-distortion signal routing in 5-V TTL-compatible digital systems requiring robust ESD/undershoot protection.

FAQ

What is the maximum undershoot voltage the SN74CBTS3384DBR can safely clamp?

The SN74CBTS3384DBR integrates Schottky diodes that clamp I/O undershoot to –0.6 V (typical) at –18 mA, with absolute minimum clamping of –1.2 V on control inputs. This protects downstream 5-V logic from negative transients caused by transmission-line reflections or hot-plug events. The SN74CBTS3384DBR's clamping specification is verified per its absolute maximum ratings table and applies across the full –40°C to +85°C operating range.

Does the SN74CBTS3384DBR support bidirectional signal flow without direction control pins?

Yes - the SN74CBTS3384DBR is a true bidirectional analog switch: signals pass equally well from A to B or B to A when the corresponding OE is low. There are no direction-control pins or internal latches; operation depends solely on OE state and voltage potential across the FET channel. This makes the SN74CBTS3384DBR ideal for passive bus architectures where data flow direction changes dynamically, such as in shared memory or peripheral arbitration schemes.

Can the SN74CBTS3384DBR be used with 3.3-V logic systems?

The SN74CBTS3384DBR requires V_CC = 4 V to 5.5 V and is not 3.3-V compatible for power supply. However, its I/O pins tolerate voltages up to 7 V (absolute max), so 3.3-V signals may pass through when V_CC = 5 V - provided the system design accounts for voltage-level mismatch on control inputs (VIH = 2 V min). For pure 3.3-V systems, TI recommends the SN74CB3Q3384 series instead. The SN74CBTS3384DBR remains a 5-V-only device.

What is the thermal resistance (θ_JA) of the SN74CBTS3384DBR in its SSOP package?

The SN74CBTS3384DBR in the DB (SSOP-24) package has a specified junction-to-ambient thermal resistance (θ_JA) of 61°C/W under standard JEDEC test conditions (JESD 51-7). This value assumes a 1-inch² copper pad with two vias and is critical for calculating maximum allowable power dissipation (P_D = (T_JMAX – T_A) / θ_JA). At 85°C ambient and 125°C max junction temperature, the SN74CBTS3384DBR supports up to ~656 mW continuous dissipation.

How does the dual-OE architecture of the SN74CBTS3384DBR improve system design flexibility?

The SN74CBTS3384DBR's two independent OE inputs (1OE and 2OE) allow granular control over two 5-bit segments - for example, enabling address lines while disabling data lines during bus arbitration, or isolating diagnostic paths from operational paths. This eliminates the need for additional logic gates or timing synchronization between segments. In practice, this architecture simplifies PCB routing, reduces component count, and improves fault containment - all inherent capabilities of the SN74CBTS3384DBR's native structure.