Texas Instruments SN74CB3Q3384ADBQR

Overview

SN74CB3Q3384ADBQR from Texas Instruments is a 10-bit FET bus switch optimized for high-bandwidth, low-voltage (2.3 V–3.6 V) digital signal routing. It features dual 5-bit independent channels with separate 1OE/2OE controls, 3 Ω typical ON-state resistance, 500 MHz bandwidth support, and 5-V tolerant I/Os-enabling rail-to-rail switching in PCI interface and memory interleaving applications.

For engineers reviewing the SN74CB3Q3384ADBQR datasheet, SN74CB3Q3384ADBQR pinout, SN74CB3Q3384ADBQR application, or SN74CB3Q3384ADBQR equivalent, key selection criteria include its bidirectional low-distortion signal gating capability, partial-power-down Ioff support, and compatibility with 2.5-V/3.3-V systems requiring sub-0.15 ns propagation delay and <5 pF OFF-state capacitance.

Technical Context

The SN74CB3Q3384ADBQR implements a charge-pump-enhanced FET architecture to maintain flat, low ON-state resistance (ron ≈ 3–8 Ω) across 0–5 V I/O voltage ranges and supply voltages from 2.3 V to 3.6 V. Its internal enable logic drives two independent 5-bit switch banks, each supporting bidirectional data flow with near-zero propagation delay (tpd = 0.09–0.15 ns) and fast enable/disable timing (ten/tdis ≤ 7.2 ns).

Designed for signal integrity in high-speed digital interconnects, it integrates undershoot clamp diodes on all control inputs, supports 0–5 V signaling with 3.3-V VCC, and delivers Ioff protection during partial power-down-preventing backflow current when VCC = 0 V and VI/O = 0–5.5 V. Its 4 pF typical OFF-state I/O capacitance minimizes loading-induced distortion on buses up to 500 MHz.

Key Specifications

Pinout & Package

SN74CB3Q3384ADBQR is housed in a 24-pin SSOP (DBQ) package, 7.9 mm × 4.4 mm, 1.2 mm max height, with 0.65 mm lead pitch and moisture sensitivity level (MSL) 2–260°C–1 year.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CB3Q3384ADBQR, SN74CBT3384CPWR trades Ioff and 5-V tolerance for lower unit cost, while PI3CHD3245LEX offers smaller footprint but sacrifices channel count, voltage flexibility, and power-down safety-making SN74CB3Q3384ADBQR optimal for robust, dual-bank, mixed-voltage interconnects.

Availability

SN74CB3Q3384ADBQR is available at Aetrix Electronics and suitable for PCI interface design, memory interleaving architectures, and low-distortion signal gating applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SN74CB3Q3384ADBQR 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 high-reliability electronic components.

The SN74CB3Q3384ADBQR belongs to TI's CB3Q family of high-bandwidth FET bus switches, engineered specifically for low-latency, low-distortion digital and analog signal routing in networking, computing, and communications infrastructure.

FAQ

What is the maximum operating frequency supported by the SN74CB3Q3384ADBQR?

The SN74CB3Q3384ADBQR supports signal bandwidths up to 500 MHz due to its low 3 Ω typical ON-state resistance and 4 pF OFF-state I/O capacitance. Its 20 MHz maximum OE switching frequency enables rapid channel enable/disable sequencing, while propagation delay remains below 0.15 ns-making SN74CB3Q3384ADBQR suitable for PCIe Gen1, DDR2, and high-speed serial interconnects.

Does the SN74CB3Q3384ADBQR support partial-power-down operation?

Yes, the SN74CB3Q3384ADBQR includes Ioff circuitry that limits backflow current to 1 µA maximum when VCC = 0 V and I/O pins are biased between 0 V and 5.5 V. This feature ensures safe hot-swap capability and prevents damage during staggered power sequencing-critical for SN74CB3Q3384ADBQR deployment in modular servers and telecom line cards.

Can the SN74CB3Q3384ADBQR interface 5-V logic signals while powered from a 3.3-V supply?

Yes, the SN74CB3Q3384ADBQR features 5-V tolerant I/Os that operate safely with input/output voltages from 0 V to 5.5 V-even when VCC is as low as 2.3 V. This allows SN74CB3Q3384ADBQR to bridge legacy 5-V peripherals and modern 3.3-V or 2.5-V controllers without external level shifters or clamping networks.

What is the pin-compatible alternative to the SN74CB3Q3384ADBQR in TSSOP package?

The SN74CB3Q3384APWR is the TSSOP (PW) packaged variant of the same device, sharing identical logic, pinout, and electrical specifications with SN74CB3Q3384ADBQR. Both devices use 24-pin layouts with matching 1OE/2OE control and A/B port assignments-enabling direct PCB footprint substitution where thermal or assembly constraints favor PW over DBQ.

How does the charge-pump circuit in the SN74CB3Q3384ADBQR improve performance?

The integrated charge pump in SN74CB3Q3384ADBQR elevates the gate voltage of internal FETs above VCC, ensuring strong turn-on across the full 0–5 V I/O range and minimizing ron variation. This results in flatter resistance (3–8 Ω), lower propagation delay (0.09–0.15 ns), and consistent rail-to-rail switching-key advantages of SN74CB3Q3384ADBQR over non-charge-pump alternatives like the CBT-series switches.