Texas Instruments SN74CB3Q3253DGVRE4

Overview

SN74CB3Q3253DGVRE4 from Texas Instruments is a dual 1-of-4 FET multiplexer-demultiplexer bus switch optimized for high-bandwidth digital and analog signal routing. It operates from 2.3 V to 3.6 V, delivers 4 Ω typical ON-state resistance (ron), supports rail-to-rail 0–5 V switching at 3.3 V VCC, and enables bidirectional data flow with <0.18 ns propagation delay. It is used in USB interface isolation and differential signal path gating where low capacitive loading (<4.5 pF B-port Cio(OFF)) and 5-V I/O tolerance are critical.

For engineers reviewing the SN74CB3Q3253DGVRE4 datasheet, SN74CB3Q3253DGVRE4 pinout, SN74CB3Q3253DGVRE4 application, or SN74CB3Q3253DGVRE4 equivalent, key selection criteria include its 500 MHz bandwidth capability, Ioff partial-power-down support, 3.5 pF typical OFF-state I/O capacitance, and compatibility with 0.8–5 V logic levels across mixed-voltage systems.

Technical Context

The SN74CB3Q3253DGVRE4 integrates two independent 1-of-4 analog/digital multiplexers, each with active-low output-enable (1OE/2OE) and 2-bit binary select (S0/S1) control. Its charge-pump-enhanced FET architecture elevates gate voltage to maintain flat ron over supply and signal voltage ranges, enabling consistent timing across 0–5 V data swings.

Each channel supports bidirectional, near-zero-delay signal routing between one common port (1A/2A) and four I/O ports (1B1–1B4 / 2B1–2B4). The device features undershoot clamp diodes on all control and data pins, 5-V tolerant I/Os regardless of VCC state, and guaranteed isolation during power-down via Ioff protection.

Key Specifications

Pinout & Package

SN74CB3Q3253DGVRE4 is packaged in a 16-pin TVSOP (DGV) with nominal body size 3.60 mm × 4.40 mm and 0.65 mm lead pitch. This ultra-thin, leaded package supports fine-pitch PCB assembly and offers thermal performance (RθJA = 126 °C/W) suitable for space-constrained industrial and communications modules.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CB3Q3253DGVRE4, SN74CBT3253PWR trades bandwidth and voltage flexibility for lower cost, while TS3DV642AIPWPR adds ESD protection at the expense of OFF-capacitance and supply range - making SN74CB3Q3253DGVRE4 optimal for mixed-voltage, high-speed infrastructure where signal fidelity and power-down safety are primary.

Availability

SN74CB3Q3253DGVRE4 is available at Aetrix Electronics and suitable for USB interface isolation, differential signal routing, video broadcast switching, and multi-format transcoder applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SN74CB3Q3253DGVRE4 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 decades of expertise in high-speed interface solutions and signal integrity engineering.

The SN74CB3Q3253DGVRE4 belongs to TI's CB3Q family of charge-pump-enhanced FET bus switches, designed specifically for high-bandwidth, low-distortion signal routing in mixed-voltage computing, communications, and broadcast infrastructure.

FAQ

What is the maximum signal frequency supported by the SN74CB3Q3253DGVRE4?

The SN74CB3Q3253DGVRE4 supports up to 500 MHz bandwidth, verified under load conditions with matched impedances and proper PCB layout. This capability enables reliable use in USB 2.0 (480 Mbps), SDI (3 Gbps), and DDR1/2 clock distribution paths where minimal phase distortion is required. Performance depends on maintaining low trace inductance and using the recommended 0.1 µF bypass capacitor at VCC.

Does the SN74CB3Q3253DGVRE4 support partial power-down operation?

Yes, the SN74CB3Q3253DGVRE4 includes Ioff circuitry that actively disables current flow between I/O pins when VCC = 0 V, preventing backfeeding and protecting upstream components during hot-swap or standby modes. This feature is validated per JESD 78 Class II latch-up testing and is intrinsic to the device's FET architecture - no external circuitry is needed to achieve safe partial-power-down behavior.

Can the SN74CB3Q3253DGVRE4 interface 3.3-V logic with 5-V peripherals?

Yes, the SN74CB3Q3253DGVRE4 supports 0–5.5 V signal levels on all I/O ports regardless of VCC voltage (2.3–3.6 V), making it ideal for interfacing 3.3-V FPGAs or microcontrollers with legacy 5-V peripherals. Its 5-V tolerant I/Os remain functional even when VCC is unpowered, and the internal charge pump ensures consistent ron across the full input voltage range without external level shifters.

What is the purpose of the charge pump in the SN74CB3Q3253DGVRE4?

The charge pump in the SN74CB3Q3253DGVRE4 elevates the gate voltage of the internal pass FETs above VCC, ensuring strong turn-on across the full 0–5 V input range and delivering flat, low ON-state resistance (4 Ω typical). This eliminates ron variation with signal swing - a critical advantage over standard MOSFET switches - and maintains signal integrity and timing predictability in high-speed digital and analog routing applications.

How does the SN74CB3Q3253DGVRE4 handle unused channels during operation?

Unused B-port channels (e.g., 1B3, 1B4) automatically enter a high-impedance OFF state when not selected by S0/S1, with Cio(OFF) limited to 3.5 pF typical - minimizing capacitive loading on shared buses. To prevent floating inputs, TI recommends tying unconnected A- or B-side pins to GND or VCC via high-value resistors (≥10 kΩ), especially in high-noise environments or when OE is asserted but no channel is selected.