Texas Instruments SN74ALVCH245DGVR

Overview

SN74ALVCH245DGVR from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between 1.65-V to 3.6-V buses. It features bus-hold circuitry on all A/B inputs, ±24-mA output drive at 3.3 V, and a maximum propagation delay of 3.4 ns at 3.3 V. It is used in voltage-level-flexible digital subsystems such as FPGA-to-ASIC interconnects and memory interface buffers.

For engineers reviewing the SN74ALVCH245DGVR datasheet, SN74ALVCH245DGVR pinout, SN74ALVCH245DGVR application, or SN74ALVCH245DGVR equivalent, key selection considerations include its 20-pin TVSOP package, DIR/OE control logic, bus-hold input retention, 3.3-V timing performance, and compatibility with mixed-voltage I/O domains.

Technical Context

The SN74ALVCH245DGVR implements dual-directional 8-bit data routing controlled by DIR (direction) and OE (output enable) inputs. Its bus-hold circuitry actively maintains valid logic states on undriven A1–A8 and B1–B8 inputs without external resistors, reducing system component count and layout complexity.

It operates across a wide supply range (1.65 V to 3.6 V), enabling interoperability between 1.8-V, 2.5-V, and 3.3-V logic families. The device achieves 3.4-ns tpd at 3.3 V with 24-mA drive strength, supporting high-speed, low-noise bus isolation in compact PCB layouts.

Key Specifications

Pinout & Package

SN74ALVCH245DGVR is housed in a 20-pin Thin Very Small Outline Package (TVSOP, DGV), measuring 4.4 mm × 6.5 mm × 1.2 mm (max height), with 0.5-mm lead pitch and moisture sensitivity level 1 (260°C peak reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245APWR, SN74ALVCH245DGVR adds bus-hold and wider 1.65–3.6-V operation but shares no pin compatibility with SN74AVC245DGVR despite identical DGV packaging-requiring careful validation of timing margins and I/O voltage constraints.

Availability

SN74ALVCH245DGVR is available at Aetrix Electronics and suitable for industrial automation interfaces, FPGA peripheral bridges, and memory expansion subsystems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for SN74ALVCH245DGVR 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 experience in high-reliability logic and interface solutions.

The SN74ALVCH245DGVR belongs to TI's ALVC/ALVCH advanced low-voltage CMOS logic family, engineered for low-power, high-speed bidirectional bus interfacing in mixed-voltage digital systems.

FAQ

What is the recommended power-up sequence for SN74ALVCH245DGVR?

TI recommends tying OE to VCC through a pullup resistor (minimum value determined by driver sink capability) to ensure outputs remain in high-impedance during power-up. VCC must be applied before any input signals, and DIR/OE should be stabilized before enabling data transfer. This prevents bus contention and ensures deterministic 3-state behavior at power-on for SN74ALVCH245DGVR.

Does SN74ALVCH245DGVR support hot-swap or live-insertion?

SN74ALVCH245DGVR supports hot-swap operation when OE is held HIGH (disabled) during insertion, preventing bus contention. Its ±100-mA latch-up immunity per JESD 78 Class II and bus-hold circuitry maintain input stability during transient contact. However, TI does not guarantee full live-insertion robustness without external current-limiting or sequencing-designers must validate under actual system conditions for SN74ALVCH245DGVR.

Can SN74ALVCH245DGVR operate with 1.8-V and 3.3-V buses simultaneously?

Yes. SN74ALVCH245DGVR operates from 1.65 V to 3.6 V and tolerates input voltages up to VCC + 0.5 V on I/O ports. When VCC = 3.3 V, it safely accepts 1.8-V logic levels on A or B ports and drives 3.3-V compatible outputs-enabling direct bidirectional interfacing between 1.8-V and 3.3-V domains without external level shifters for SN74ALVCH245DGVR.

How does the bus-hold feature affect PCB layout for SN74ALVCH245DGVR?

The bus-hold circuitry in SN74ALVCH245DGVR actively maintains valid logic states on undriven A1–A8 and B1–B8 inputs, eliminating the need for external pullup or pulldown resistors. This reduces PCB real estate, BOM count, and potential noise coupling paths-allowing longer stubs and relaxed routing rules compared to non-bus-hold transceivers, provided trace capacitance remains within 12 pF (Cio spec) for SN74ALVCH245DGVR.

What is the thermal performance of SN74ALVCH245DGVR in its DGV package?

SN74ALVCH245DGVR in the TVSOP (DGV) package has a junction-to-ambient thermal resistance (θJA) of 92°C/W, measured per JESD 51-7 on a standard 1-in² 2-layer board. At 24-mA drive and 3.3-V supply, typical power dissipation is <15 mW per channel-keeping junction temperature rise below 15°C under normal operation, making forced cooling unnecessary for SN74ALVCH245DGVR in most industrial layouts.