Texas Instruments SN74LVTH245ANSRG4

Overview

SN74LVTH245ANSRG4 from Texas Instruments is a 3.3-V ABT octal bus transceiver with 3-state outputs, designed for bidirectional asynchronous data transfer between 3.3-V and 5-V buses. It features bus-hold circuitry on all A/B data inputs, I_off support for hot insertion, and operates across V_CC = 2.7–3.6 V. Used in mixed-voltage system interconnects such as industrial PLC backplanes and legacy-to-modern interface bridges.

For engineers reviewing the SN74LVTH245ANSRG4 datasheet, SN74LVTH245ANSRG4 pinout, SN74LVTH245ANSRG4 application, or SN74LVTH245ANSRG4 equivalent, key selection criteria include its 20-pin SOP (NS) package, ±100 µA I_off current at V_CC = 0 V, 3.5 ns typical propagation delay (t_PLH/t_PHL), bus-hold input stabilization, and compatibility with 5-V-tolerant inputs while powered from 3.3 V.

Technical Context

This device implements an active-high direction-control (DIR) and active-low output-enable (OE) logic architecture to route data either from A-to-B or B-to-A. Its ABT (Advanced BiCMOS Technology) core delivers TTL-compatible output drive (±64 mA I_OL/I_OH) while maintaining 3.3-V supply operation and supporting unregulated battery input down to 2.7 V.

The integrated bus-hold circuitry provides ±750 µA dynamic hold current (V_CC = 3.6 V), eliminating external pullup/pulldown resistors on floating data lines. Power-up 3-state and I_off protection ensure safe hot-insertion into live backplanes without bus contention or backdrive damage.

Key Specifications

Pinout & Package

SOP-20 (NS) package: 12.8 mm × 7.5 mm body, 1.27 mm pitch, gull-wing leads, RoHS-compliant NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245A and SN74ALVC245, the SN74LVTH245ANSRG4 uniquely combines 5-V-tolerant I/O, integrated bus-hold, and I_off-enabled hot insertion-making it the only option among the three qualified for mixed-voltage backplane interconnects requiring zero external bias components and field-serviceability.

Availability

SN74LVTH245ANSRG4 is available at Aetrix Electronics and suitable for industrial automation, test equipment, and embedded computing applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for SN74LVTH245ANSRG4 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 delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The SN74LVTH245A product line targets mixed-voltage system interconnects, specifically addressing design challenges in legacy-to-modern interface bridging, hot-swappable modules, and noise-sensitive industrial backplanes.

FAQ

What is the recommended power-up sequence for SN74LVTH245ANSRG4 to avoid bus contention?

OE must be held high (inactive) until V_CC reaches ≥2.7 V and stabilizes; TI recommends tying OE to V_CC via a pullup resistor (minimum value determined by driver sink capability). This ensures the SN74LVTH245ANSRG4 remains in 3-state during power ramp-up, preventing conflicts on shared A/B buses. The built-in power-up 3-state circuitry enforces this behavior even without external biasing.

Does SN74LVTH245ANSRG4 support true 5-V operation on its I/O pins when V_CC = 3.3 V?

Yes - the SN74LVTH245ANSRG4 supports 5-V-tolerant inputs and outputs while powered from 3.3 V. Input voltage range is specified to 5.5 V, and output clamp ratings extend to 7 V in high-impedance state. This allows direct connection to 5-V logic without external level shifters, provided V_CC remains within 2.7–3.6 V.

Can bus-hold circuitry on SN74LVTH245ANSRG4 be disabled or bypassed?

No - bus-hold is permanently enabled on all A and B port inputs and cannot be disabled. TI explicitly warns against using external pullup/pulldown resistors with the SN74LVTH245ANSRG4, as they conflict with the internal ±750 µA hold current and may cause excessive power draw or logic instability. Unused inputs should be left floating to leverage bus-hold.

What thermal performance can be expected from SN74LVTH245ANSRG4 in SOP-20 (NS) package?

The SN74LVTH245ANSRG4 in SOP-20 (NS) package has a θ_JA of 60°C/W under standard JEDEC conditions. At full 64 mA output drive per pin (worst-case), total power dissipation remains ≤5 mA ICC (quiescent) + ~120 mW dynamic load, resulting in junction temperature rise <10°C above ambient - well within safe operating limits for industrial applications up to 85°C ambient.

Is SN74LVTH245ANSRG4 pin-compatible with other packages in the SN74LVTH245A family?

Yes - all SN74LVTH245A variants, including SN74LVTH245ANSRG4 (SOP-20), SN74LVTH245ADBR (SSOP-20), and SN74LVTH245APWR (TSSOP-20), share identical 20-pin functional pinout and electrical characteristics. Mechanical footprint differs, but signal mapping (A1–A8, DIR, GND, B1–B8, OE, V_CC) is consistent across packages, enabling layout reuse with land-pattern adaptation.