Texas Instruments SN74LVC2952ADBR

Overview

SN74LVC2952ADBR from Texas Instruments is an octal bus transceiver and register with 3-state outputs, designed for bidirectional data flow between two 8-bit buses in mixed-voltage systems. It operates from 1.65 V to 3.6 V, supports 5.5-V-tolerant inputs, delivers 8.2 ns max propagation delay at 3.3 V, and features Ioff partial-power-down protection. It is used in level-shifting interfaces between 3.3-V and 5-V logic domains in industrial control backplanes.

For engineers reviewing the SN74LVC2952ADBR datasheet, SN74LVC2952ADBR pinout, SN74LVC2952ADBR application, or SN74LVC2952ADBR equivalent, key selection criteria include bidirectional registered data transfer, 3.3-V/5-V mixed-mode compatibility, 24-pin SSOP package constraints, and Ioff-enabled power sequencing in hot-swap-capable systems.

Technical Context

The SN74LVC2952ADBR integrates two independent 8-bit back-to-back registers enabling synchronous latching of A-to-B or B-to-A data on the low-to-high clock edge when the corresponding clock-enable input is low. Its dual-directional control logic (CLKAB/CLKENAB/OEAB and CLKBA/CLKENBA/OEBA) allows independent timing and output gating per bus direction.

It implements true 3-state outputs with guaranteed high-impedance during power-up/down when OE is pulled up to VCC, and its Ioff circuitry actively disables outputs to prevent backflow current when VCC = 0 V - a requirement for partial-power-down compliance in multi-rail systems.

Key Specifications

Pinout & Package

SN74LVC2952ADBR uses a 24-pin SSOP (DB) package with 0.65-mm lead pitch, 7.8-mm body width, and 1.2-mm maximum height - optimized for high-density PCB layouts requiring thermal efficiency and reflow compatibility.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal registered transceiver applications.

Compared with SN74LVC2952APWR, the SN74LVC2952ADBR offers identical functionality in a wider SSOP package suitable for manual assembly and thermal dissipation in industrial backplanes; versus SN74ALVC162952GR, it provides half the bus width but fits existing 24-pin layouts without redesign.

Availability

SN74LVC2952ADBR is available at Aetrix Electronics and suitable for industrial backplane interfaces, hot-swappable module interconnects, and memory expansion bridges requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for SN74LVC2952ADBR 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 logic solutions, with decades of expertise in high-reliability interface ICs for industrial and automotive markets.

The SN74LVC2952ADBR belongs to TI's LVC logic family, engineered for low-voltage, mixed-signal interoperability in systems demanding robust voltage translation, precise timing control, and power-aware design.

FAQ

What is the primary function of the SN74LVC2952ADBR?

The SN74LVC2952ADBR is an octal bus transceiver and register with 3-state outputs, enabling synchronous, bidirectional data transfer between two 8-bit buses. It latches data on rising clock edges and provides independent output enable control per direction. Its design supports mixed 3.3-V/5-V system interfacing while maintaining timing integrity and power sequencing safety - making SN74LVC2952ADBR ideal for industrial backplane and modular interface applications.

Does the SN74LVC2952ADBR support partial-power-down operation?

Yes, the SN74LVC2952ADBR includes Ioff circuitry that disables outputs when VCC = 0 V, preventing damaging current backflow during power-up/down sequences. This feature is explicitly verified in TI's datasheet and enables safe use in hot-swap and multi-rail systems. The Ioff leakage is specified at ±10 µA when VI or VO = 5.5 V, confirming robust isolation - a critical capability for SN74LVC2952ADBR in industrial power-managed architectures.

What package type is used for the SN74LVC2952ADBR?

The SN74LVC2952ADBR uses a 24-pin SSOP (Shrink Small Outline Package) with designation DB, measuring 7.8 mm × 5.3 mm with 0.65-mm lead pitch and 1.2-mm maximum height. This package is RoHS-compliant, moisture-sensitive level 1, and supplied in tape-and-reel format (2000 units per reel). Its dimensions and thermal characteristics (θJA = 63°C/W) are documented in TI's official DB package drawing MSSO002E - confirming mechanical compatibility for SN74LVC2952ADBR in high-density industrial PCB layouts.

Can the SN74LVC2952ADBR interface 5-V logic signals while powered at 3.3 V?

Yes, the SN74LVC2952ADBR accepts input voltages up to 5.5 V while operating from a 1.65–3.6-V VCC supply, enabling direct connection to 5-V TTL or CMOS outputs without external level shifters. Input thresholds scale with VCC (e.g., VIH ≥ 0.65×VCC), and the device maintains full timing specifications under mixed-mode conditions - a core specification confirmed in TI's SCAS311I datasheet. This makes SN74LVC2952ADBR especially valuable in legacy system upgrades where 5-V peripherals coexist with 3.3-V controllers.

What are the timing-critical control inputs for the SN74LVC2952ADBR?

The SN74LVC2952ADBR relies on three per-direction control inputs: CLKAB/CLKBA (rising-edge clock), CLKENAB/CLKENBA (active-low clock enable), and OEAB/OEBA (active-low output enable). Setup/hold times are specified at 1.3–1.7 ns (tsu) and 1.1–1.4 ns (th) over VCC range, with max tpd of 8.2 ns at 3.3 V. These parameters are measured under defined load conditions (CL = 50 pF) and define the minimum clock period for reliable registered transfer - essential for designing timing-critical interfaces using SN74LVC2952ADBR.