Texas Instruments SN74LVCH245ARGYRG4

Overview

SN74LVCH245ARGYRG4 from Texas Instruments is an octal bus transceiver with tri-state outputs, designed for bidirectional data translation between 1.65-V and 3.6-V logic domains while accepting 5-V-tolerant inputs. It features 20-pin VQFN packaging, Ioff support for live insertion, bus-hold on all data inputs, and a max propagation delay of 6.3 ns at 3.3 V. It enables robust signal isolation in mixed-voltage server backplanes and embedded interface bridges.

For engineers reviewing the SN74LVCH245ARGYRG4 datasheet, SN74LVCH245ARGYRG4 pinout, SN74LVCH245ARGYRG4 application, or SN74LVCH245ARGYRG4 equivalent, key selection criteria include its 5-V input tolerance, Ioff-enabled partial-power-down capability, bus-hold functionality eliminating external resistors, and guaranteed timing performance across –40°C to 125°C.

Technical Context

This device implements asynchronous bidirectional data transfer between two 8-bit buses (A and B ports) controlled by DIR (direction) and OE (output enable, active-low). Its CMOS input structure supports mixed-mode operation: inputs tolerate up to 5.5 V regardless of VCC (1.65–3.6 V), enabling safe interfacing between 3.3-V microcontrollers and legacy 5-V peripherals.

The integrated bus-hold circuit maintains valid logic states on floating A/B inputs without external biasing, and the Ioff feature actively disables outputs during power-down to prevent back-drive current-critical for hot-swap and multi-rail system designs. All specifications are validated per JEDEC JESD78 and JESD22 standards.

Key Specifications

Pinout & Package

SN74LVCH245ARGYRG4 uses a 20-pin VQFN package (RGY suffix) with 4.5 mm × 3.5 mm body size and 0.5-mm pitch. Exposed thermal pad enhances thermal dissipation (RθJA = 41.4°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245A and 74AVC8T245, SN74LVCH245ARGYRG4 uniquely combines 5-V input tolerance, bus-hold, and Ioff in a thermally efficient VQFN package-making it the only choice for mixed-voltage industrial backplanes requiring zero-BOM overhead and hot-swap resilience.

Availability

SN74LVCH245ARGYRG4 is available at Aetrix Electronics and suitable for server backplanes, industrial PLC I/O modules, wearable health sensor hubs, and telecom line card management requiring stable component supply across extended temperature and mixed-voltage environments.

Supply support for SN74LVCH245ARGYRG4 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 solutions for industrial, automotive, and communications markets.

SN74LVCH245ARGYRG4 belongs to TI's LVCH logic family, engineered for robust mixed-signal interfacing in harsh environments-emphasizing voltage translation, power-aware isolation, and long-term reliability over raw speed.

FAQ

What is the maximum input voltage rating for SN74LVCH245ARGYRG4?

SN74LVCH245ARGYRG4 accepts input voltages up to 5.5 V on all A and B port pins, independent of VCC supply voltage (1.65–3.6 V). This 5-V tolerance enables direct interfacing with legacy TTL or 5-V CMOS devices without external level shifters, and is verified per Absolute Maximum Ratings in the official TI datasheet SCES008Q.

Does SN74LVCH245ARGYRG4 support hot-plug operation?

Yes, SN74LVCH245ARGYRG4 supports hot-plug via its Ioff feature: when VCC = 0 V, input and output leakage remains limited to ±20 µA, preventing damaging back-current flow. This behavior is tested per JESD78 and explicitly documented for partial-power-down applications in the TI datasheet SCES008Q.

How does the bus-hold function work on SN74LVCH245ARGYRG4?

SN74LVCH245ARGYRG4 integrates active bus-hold circuitry on all A1–A8 and B1–B8 pins, maintaining valid logic states (±75 µA hold current at 3 V) on floating inputs without external resistors. This feature is always active-unaffected by OE or DIR-and eliminates BOM cost and layout complexity in systems with unterminated data paths.

What is the thermal resistance (RθJA) of SN74LVCH245ARGYRG4 in its VQFN package?

SN74LVCH245ARGYRG4 in the RGY (VQFN-20) package has a junction-to-ambient thermal resistance (RθJA) of 41.4°C/W, as specified in Table 6.5 of the TI datasheet SCES008Q. This value assumes standard JEDEC 2-layer board conditions and confirms suitability for thermally constrained applications such as dense telecom line cards.

Can SN74LVCH245ARGYRG4 operate at 1.65 V VCC while driving 50-pF loads?

Yes, SN74LVCH245ARGYRG4 is fully characterized down to 1.65 V VCC, including switching performance: at VCC = 1.8 V ±0.15 V and CL = 50 pF, tPLH/tPHL is guaranteed ≤9.5 ns (–40°C to 125°C). This enables reliable operation in ultra-low-power portable systems while meeting timing margins for SPI and parallel bus protocols.