Texas Instruments SN74CB3Q3245DGVR

Overview

SN74CB3Q3245DGVR from Texas Instruments is an 8-bit FET bus switch optimized for high-bandwidth, low-voltage digital signal routing in 2.5-V/3.3-V systems. It provides bidirectional rail-to-rail switching with 4 Ω typical ON-state resistance, 3.5 pF typical OFF-state I/O capacitance, and supports 0- to 5-V signaling levels while powered at 2.3–3.6 V. It is used in PCI interface isolation and memory interleaving applications requiring minimal propagation delay and partial-power-down capability.

For engineers reviewing the SN74CB3Q3245DGVR datasheet, SN74CB3Q3245DGVR pinout, SN74CB3Q3245DGVR application, or SN74CB3Q3245DGVR equivalent, key selection criteria include its 20-pin TVSOP (DGV) package, Ioff-enabled partial-power-down operation, 5-V tolerant I/Os, and sub-0.2 ns propagation delay under 3.3-V operation - critical for high-speed bus gating and differential signal interface design.

Technical Context

The SN74CB3Q3245DGVR implements a charge-pump-enhanced FET architecture to elevate gate voltage and maintain flat, low ON-state resistance (ron ≈ 4–8 Ω) across input voltage range (0–5.5 V), enabling rail-to-rail analog/digital signal pass-through. Its single OE control input enables/disables all eight A↔B channels simultaneously with near-zero propagation delay (tpd ≤ 0.20 ns).

Designed for system-level bus isolation, it features Ioff circuitry that blocks current backflow during power-down, 5-V tolerant I/Os regardless of VCC state, and undershoot clamp diodes on data/control pins. The device operates over –40°C to 85°C and meets JESD 78 Class II latch-up and JESD 22 HBM/CDM ESD specifications.

Key Specifications

Pinout & Package

SN74CB3Q3245DGVR uses a 20-pin Thin Very Small Outline Package (TVSOP, DGV), 4.4 mm × 6.5 mm body, 0.65 mm pitch, 1.2 mm max height, with exposed thermal pad (not electrically connected). Pin 1 index located at top-left corner; tape orientation quadrant Q1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit FET bus switch applications.

Compared with IDTQS3VH384PAG and SN74CB3Q3245PWR, SN74CB3Q3245DGVR delivers superior thermal dissipation (θJA = 92°C/W), smaller PCB area (4.4 × 6.5 mm), and integrated thermal pad - making it optimal for compact, high-density, and thermally demanding applications like embedded networking and portable instrumentation.

Availability

SN74CB3Q3245DGVR is available at Aetrix Electronics and suitable for PCI interface isolation, memory interleaving, differential signal routing, and low-distortion analog gating requiring stable component supply across industrial, communications, and computing platforms.

Supply support for SN74CB3Q3245DGVR 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 delivering analog, embedded processing, and connectivity solutions with focus on reliability, scalability, and system-level integration.

The SN74CB3Q3245DGVR belongs to TI's CB3Q family of high-bandwidth FET bus switches, engineered specifically for low-latency, low-distortion signal routing in broadband communications, networking infrastructure, and data-intensive computing systems.

FAQ

What is the maximum operating frequency supported by SN74CB3Q3245DGVR?

The SN74CB3Q3245DGVR supports up to 500 MHz bandwidth in its data path, verified by TI's characterization of signal integrity and ON-state resistance flatness. Its 20 MHz maximum OE switching frequency (fOE) and sub-0.2 ns propagation delay ensure reliable operation in high-speed bus gating applications such as PCI Express Gen 1 and DDR1 memory interfaces. Bandwidth is maintained across 0–5 V signal swings with minimal distortion.

Does SN74CB3Q3245DGVR support partial-power-down mode?

Yes, SN74CB3Q3245DGVR fully supports partial-power-down mode via its Ioff feature. When VCC = 0 V, Ioff limits current backflow to ≤1 µA per I/O, preventing damage to powered-down sections of the system. This capability is validated per JESD 78 Class II latch-up standards and enables safe hot-swap and multi-rail power sequencing in servers and telecom equipment using SN74CB3Q3245DGVR.

What is the recommended OE pin handling during power-up for SN74CB3Q3245DGVR?

TI recommends tying OE to VCC through a pullup resistor during power-up to ensure the SN74CB3Q3245DGVR starts in high-impedance (OFF) state. The minimum resistor value depends on the driver's sink capability; typical values range from 4.7 kΩ to 10 kΩ. This prevents unintended bus connection before system initialization completes - a critical requirement for deterministic boot sequences in embedded controllers using SN74CB3Q3245DGVR.

Can SN74CB3Q3245DGVR interface between 1.8-V and 5-V logic domains?

Yes, SN74CB3Q3245DGVR supports 0–5.5 V signaling on all A and B I/O ports regardless of VCC (2.3–3.6 V), enabling direct interfacing between 1.8-V, 2.5-V, 3.3-V, and 5-V logic families. Its 5-V tolerant I/Os eliminate external level shifters in mixed-voltage systems. This capability is confirmed in TI's SCDS124B datasheet and applies directly to SN74CB3Q3245DGVR without derating or additional components.

What is the thermal performance of SN74CB3Q3245DGVR in its TVSOP package?

SN74CB3Q3245DGVR in the TVSOP (DGV) package has a thermal impedance θJA of 92°C/W, measured per JESD 51-7. Its exposed thermal pad enhances heat transfer to the PCB; TI recommends soldering the pad to a solid copper plane for optimal thermal performance. Under typical 1 mA ICC load and 25°C ambient, junction temperature rise remains below 10°C - ensuring stable operation in compact, fanless enclosures where SN74CB3Q3245DGVR is deployed.