Texas Instruments SN74LVCHR16245AKR

Overview

SN74LVCHR16245AKR from Texas Instruments is a 16-bit dual-octal noninverting bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between 1.65-V to 3.6-V buses. It supports mixed-mode signal operation (5.5-V-tolerant inputs with 3.3-V VCC), features integrated 26-Ω output series resistors, bus-hold on all data I/Os, and Ioff for live insertion. Used in telecom infrastructure backplanes and industrial transport control modules.

For engineers reviewing the SN74LVCHR16245AKR datasheet, SN74LVCHR16245AKR pinout, SN74LVCHR16245AKR application, or SN74LVCHR16245AKR equivalent, key selection criteria include its 4.8 ns max propagation delay at 3.3 V, 12 mA output drive capability per channel, 5.5-V input tolerance, and dual independent DIR/OE control enabling flexible 8-bit or 16-bit bus isolation in multi-voltage systems.

Technical Context

This device implements two independent 8-bit transceiver sections-each with dedicated direction (DIR) and output-enable (OE) controls-allowing simultaneous A→B and B→A data flow under separate logic supervision. Its bus-hold circuitry actively maintains valid logic states on floating data inputs without external resistors, and Ioff protection disables outputs when VCC = 0 V to prevent back-drive current.

The 26-Ω on-die series termination at each output reduces overshoot/undershoot and eliminates need for external damping resistors. Input voltage tolerance up to 5.5 V enables direct interfacing with legacy 5-V logic while operating from 1.65–3.6 V supplies, making it suitable for voltage translation in mixed-supply server and test equipment backplanes.

Key Specifications

Pinout & Package

TSSOP-48 package (12.50 mm × 6.10 mm body size) with exposed thermal pad; pin-compatible with SSOP (DL) and TVSOP (DGV) variants. Pin numbering follows JEDEC MS-012 standard top-view layout.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVCHR16245AKR, SN74LVC16245A lacks critical industrial reliability features (bus-hold, Ioff, 5.5-V tolerance), while SN74AVC16245 trades voltage flexibility and robustness for speed and ultra-low-voltage support-neither matches the balanced mixed-signal interface capability of the LVCHR variant.

Availability

SN74LVCHR16245AKR is available at Aetrix Electronics and suitable for telecom infrastructures, industrial transport control modules, and server memory subsystems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LVCHR16245AKR 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 company specializing in analog and embedded processing technologies, with leadership in interface, power management, and signal chain ICs for industrial, automotive, and communications markets.

The SN74LVCHR16245AKR belongs to TI's Widebus™ family of advanced bus interface devices, engineered specifically for robust, low-power, mixed-voltage data routing in mission-critical infrastructure equipment.

FAQ

What voltage levels can the SN74LVCHR16245AKR inputs tolerate?

The SN74LVCHR16245AKR inputs accept voltages up to 5.5 V regardless of VCC setting (1.65–3.6 V), enabling direct interfacing with 5-V logic families without external level-shifting circuitry. This absolute 5.5-V tolerance is specified across the full operating temperature range and is distinct from typical "VCC + 0.5 V" limits found in standard LVC devices.

Does the SN74LVCHR16245AKR require external pullup or pulldown resistors on unused data lines?

No. The SN74LVCHR16245AKR integrates active bus-hold circuitry on all data I/Os (A1–A8, B1–B8), which maintains the last-valid logic state with ±75 µA hold current. Using external resistors with enabled bus-hold is explicitly discouraged in the datasheet, as it may cause contention or excessive current draw.

How does the Ioff feature of the SN74LVCHR16245AKR protect the system during partial power-down?

The Ioff circuitry in the SN74LVCHR16245AKR disables all outputs when VCC = 0 V, limiting leakage current to ±10 µA. This prevents damaging back-current flow from powered buses (e.g., 5-V side) into unpowered sections (e.g., 3.3-V MCU domain), enabling safe hot-swap and modular power sequencing in rack-mounted systems.

What is the maximum data rate supported by the SN74LVCHR16245AKR in a typical 3.3-V application?

With a maximum propagation delay of 4.8 ns at 3.3 V and guaranteed 12 mA drive strength, the SN74LVCHR16245AKR supports reliable data rates exceeding 100 MHz in point-to-point configurations. System-level timing must account for PCB trace length, load capacitance, and signal integrity-TI's application note SBAA222 provides validated layout guidelines for >80-MHz operation.

Can the SN74LVCHR16245AKR be used as two independent 8-bit transceivers?

Yes. The SN74LVCHR16245AKR contains two fully independent 8-bit transceiver sections (Section 1: A1–A8/B1–B8/1DIR/1OE; Section 2: A1–A8/B1–B8/2DIR/2OE), each with dedicated direction and output-enable controls. This allows simultaneous bidirectional data flow in different directions-for example, A→B on Section 1 while B→A on Section 2-without cross-talk or shared timing constraints.