Texas Instruments SN74LVTH2245NSR

Overview

SN74LVTH2245NSR from Texas Instruments is an octal bus transceiver designed for 3.3-V V_CC operation with mixed-mode 5-V input/output tolerance, enabling TTL-level interfacing between 3.3-V and 5-V data buses. It supports bidirectional data flow (A↔B), features bus-hold on all data inputs, integrated 22-Ω B-port series termination, and I_off/power-up 3-state for hot insertion in industrial backplane and legacy interface applications.

For engineers reviewing the SN74LVTH2245NSR datasheet, SN74LVTH2245NSR pinout, SN74LVTH2245NSR application, or SN74LVTH2245NSR equivalent, key selection criteria include its 20-pin SOP (NS) package, ±12 mA B-port drive, 2.7–3.6 V supply range, bus-hold current specification (±75 µA at V_CC = 3 V), and propagation delays under 5.1 ns (V_CC = 3.3 V).

Technical Context

This device implements a dual-supply-tolerant transceiver architecture with independent direction (DIR) and output-enable (OE) control logic. Its A-port supports up to 64 mA sink / 32 mA source, while B-port outputs integrate 22-Ω series resistors to suppress overshoot/undershoot without external components.

The bus-hold circuit maintains unused inputs at valid logic levels (±75 µA hold current at V_CC = 3 V), eliminating external pull resistors. I_off protection limits reverse current during power-down, and power-up 3-state ensures high-impedance outputs when V_CC < 1.5 V.

Key Specifications

Pinout & Package

SN74LVTH2245NSR uses a 20-pin SOP (Small Outline Package) with 0.65 mm lead pitch and 7.5 mm × 12.8 mm body dimensions per TI package drawing NS0020A. The package is RoHS-compliant, moisture sensitivity level 1, and rated for −40°C to +85°C operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVTH2245NSR, SN74LVC2245APW lacks bus-hold and B-port series resistors-requiring external components for equivalent functionality-while SN74ALVC162245DGGR provides double the data width but demands PCB redesign due to incompatible 48-pin TSSOP packaging.

Availability

SN74LVTH2245NSR is available at Aetrix Electronics and suitable for industrial backplane interfaces, legacy system upgrade bridges, hot-swappable module interfaces, and low-power embedded data links requiring stable component supply across extended temperature ranges.

Supply support for SN74LVTH2245NSR 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 over 90 years of innovation in industrial, automotive, and communications markets.

The SN74LVTH series targets mixed-voltage system interfacing, delivering robust 5-V tolerant I/O on 3.3-V rails with enhanced ESD/latch-up performance and hot-swap readiness for mission-critical infrastructure.

FAQ

What is the maximum operating temperature range for SN74LVTH2245NSR?

The SN74LVTH2245NSR is specified for operation from −40°C to +85°C ambient temperature, aligning with industrial-grade requirements. This range is confirmed in the "recommended operating conditions" table of the SCBS707E datasheet and applies specifically to the NS package variant.

Does SN74LVTH2245NSR require external pull-up resistors on its data inputs?

No, SN74LVTH2245NSR includes active bus-hold circuitry on all A- and B-port data inputs, which maintains floating inputs at valid logic levels. Using external pull-up or pull-down resistors with SN74LVTH2245NSR is explicitly discouraged per the datasheet to avoid conflicting currents.

Can SN74LVTH2245NSR safely interface a 3.3-V microcontroller with a 5-V peripheral?

Yes, SN74LVTH2245NSR supports mixed-mode operation: its inputs accept 0–5.5 V signals while powered from a 2.7–3.6 V V_CC, and its outputs drive 5-V TTL-compatible levels. This allows direct, level-shift-free communication between 3.3-V and 5-V domains without additional circuitry.

What is the purpose of the 22-Ω series resistors on the B-port outputs of SN74LVTH2245NSR?

The integrated 22-Ω series resistors on SN74LVTH2245NSR's B-port outputs reduce signal overshoot and undershoot caused by transmission-line effects, improving signal integrity on unterminated or moderately loaded buses. They eliminate the need for discrete series termination resistors in most applications.

Is SN74LVTH2245NSR suitable for hot-plug applications?

Yes, SN74LVTH2245NSR incorporates I_off circuitry and power-up 3-state functionality, both verified per JEDEC standards. These features disable outputs during power-down and ensure high-impedance states at power-up, preventing damaging current backflow in hot-insertion systems like modular telecom or industrial backplanes.