Texas Instruments SN74CBT3383PW

Overview

SN74CBT3383PW from Texas Instruments is a 10-bit TTL-compatible bus-exchange switch in TSSOP-24 package, featuring 5 Ω typical ON-state resistance, 200 MHz bandwidth, bidirectional near-zero-delay signal routing, and dual-mode operation (bus switch or 5-bit nibble swap) for enterprise server memory interconnects.

For engineers reviewing the SN74CBT3383PW datasheet, SN74CBT3383PW pinout, SN74CBT3383PW application, or SN74CBT3383PW equivalent, key selection criteria include VCC operating range (4.5–5.5 V), BE/BX control logic compatibility with 3.3-V/5-V CMOS/TTL, low 6 pF OFF-state capacitance, and thermal performance (RθJA = 88 °C/W) in space-constrained server backplane designs.

Technical Context

The SN74CBT3383PW implements a passive FET-based analog switch architecture with no internal level-shifting or buffering-signal integrity relies on external rail stability and layout-controlled trace impedance. Its functional modes are strictly determined by two digital control inputs: BE (active-low enable) and BX (bus exchange select), enabling either direct A↔B pass-through or cross-connected 1A1↔1B2/1A2↔1B1 routing.

All 10 channels operate simultaneously with matched rON (5–7 Ω typical), flat frequency response up to 200 MHz, and symmetrical I/O loading (Cio(OFF) = 6 pF). Propagation delay is RC-limited (tpd ≤ 1 ns at CL = 50 pF), and switching is fully bidirectional with no direction pin or internal biasing required.

Key Specifications

Pinout & Package

TSSOP-24 package (7.80 mm × 4.40 mm, 1.2 mm max height), RoHS-compliant, NIPDAU lead finish, MSL Level-1 (unlimited reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBTD3383PW and SN74LVC1G3157DCKR, the SN74CBT3383PW uniquely delivers 10-bit synchronized bus exchange at 5 Ω rON and 200 MHz bandwidth in a single TSSOP-24 package-making it irreplaceable for high-fidelity, low-latency memory and fabric interconnects requiring hardware-level nibble swapping.

Availability

SN74CBT3383PW is available at Aetrix Electronics and suitable for enterprise servers, Ethernet switches, and industrial PCs requiring stable component supply with long-term lifecycle support and traceable sourcing.

Supply support for SN74CBT3383PW 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 50 years of innovation in high-reliability logic and interface solutions.

The SN74CBT3383PW belongs to TI's CBT (Crosspoint Bus Transceiver) family, engineered specifically for low-latency, high-fidelity bus switching in mission-critical computing infrastructure where signal integrity and deterministic timing outweigh programmability.

FAQ

What is the maximum operating frequency supported by the SN74CBT3383PW?

The SN74CBT3383PW is characterized for operation up to 200 MHz, verified under standard test conditions (CL = 50 pF, VCC = 5 V, TA = 25°C). Real-world performance depends on PCB layout, trace impedance, and load capacitance-TI recommends keeping total node capacitance below 10 pF for reliable 200-MHz operation. The SN74CBT3383PW achieves this through its 6-pF OFF-state capacitance and 5-Ω ON-resistance.

Can the SN74CBT3383PW be used with 3.3-V logic inputs while powered at 5 V?

Yes, the SN74CBT3383PW accepts 3.3-V CMOS logic levels on BE and BX control pins when VCC = 5 V, as confirmed by VIH(min) = 2.0 V and VIL(max) = 0.8 V in the Recommended Operating Conditions table. This allows direct interfacing with 3.3-V microcontrollers or FPGAs without level-shifting circuitry-critical for mixed-voltage server board designs using the SN74CBT3383PW.

Does the SN74CBT3383PW require external pull-up or pull-down resistors on BE or BX?

No external resistors are required. The SN74CBT3383PW has no internal weak pull-ups or pull-downs, but BE and BX are standard CMOS inputs with negligible leakage (±1 µA). In practice, BE should be actively driven low to enable switching; leaving it floating risks undefined behavior. TI recommends driving BE and BX directly from system logic-no external biasing is needed for stable SN74CBT3383PW operation.

How does the bus exchange (BX) function affect signal timing in the SN74CBT3383PW?

Activating BX (high) swaps nibble pairs (e.g., 1A1↔1B2) but introduces no additional propagation delay-the SN74CBT3383PW maintains identical tpd ≤ 1 ns in both direct and exchanged modes. This is because the exchange is implemented via internal metal routing, not active logic; timing remains RC-limited solely by rON and load capacitance. Thus, the SN74CBT3383PW supports real-time bus reconfiguration without violating setup/hold windows.

Is the SN74CBT3383PW pin-compatible with other packages in the same family?

No-while SN74CBT3383PW shares identical logic and electrical specifications with SN74CBT3383DB (SSOP), SN74CBT3383DW (SOIC), and SN74CBT3383PWR (TSSOP tape-and-reel), the TSSOP-24 (PW) package has distinct mechanical dimensions (7.80 mm × 4.40 mm) and land pattern requirements. PCB layout must follow TI's PW0024A outline; direct substitution without board revision is not possible-even though the SN74CBT3383PW pinout matches other 24-pin variants electrically.