Texas Instruments SN65HVD74DR

Overview

SN65HVD74DR from Texas Instruments is a 3.3-V full-duplex RS-485 transceiver with ±12-kV IEC 61000-4-2 contact ESD protection, 20-Mbps signaling rate, 70-mV receiver hysteresis, and <1.1-mA quiescent current - deployed in industrial automation networks requiring robust noise immunity and hot-plug operation.

For engineers reviewing the SN65HVD74DR datasheet, SN65HVD74DR pinout, SN65HVD74DR application, or SN65HVD74DR equivalent, key selection criteria include its SOIC-8/MSOP-8 package compatibility, driver/receiver enable architecture (no external enables), bus I/O voltage tolerance (–7 V to 12 V), and thermal shutdown at 170°C for overtemperature safety in harsh environments.

Technical Context

The SN65HVD74DR integrates a differential driver and differential receiver operating from a single 3.3-V supply (3.0–3.6 V), with separate A/B bus inputs and Y/Z bus outputs enabling true full-duplex communication. Its receiver features 70-mV hysteresis and supports common-mode input range of –7 V to 12 V, ensuring reliable operation across long cable runs and multi-point topologies.

Unlike SN65HVD70/73/76 variants, SN65HVD74DR has no driver-enable (DE) or receiver-enable (RE) pins - it is fully enabled by default. This simplifies control logic but eliminates low-power standby modes (<5 µA), distinguishing it from enable-capable family members used in power-sensitive applications.

Key Specifications

Pinout & Package

SN65HVD74DR is available in SOIC-8 (D) and MSOP-8 (DGK) packages, both measuring 3.00 mm × 3.00 mm (MSOP) or 4.90 mm × 3.91 mm (SOIC). Pin functions are identical across both packages.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar RS-485 transceiver applications.

Compared with SN65HVD73DR, SN65HVD74DR offers simpler control (no enable logic) but higher active current; versus THVD1550DR, it provides lower cost and smaller footprint but lacks integrated regulation and fault reporting - making SN65HVD74DR optimal for cost-sensitive, always-on industrial nodes.

Availability

SN65HVD74DR is available at Aetrix Electronics and suitable for industrial automation, building management, and smart metering applications requiring stable component supply, extended temperature operation, and high-noise immunity.

Supply support for SN65HVD74DR 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 communications markets.

The SN65HVD7x product line was designed specifically for rugged RS-485 communication in harsh environments - emphasizing ESD robustness, wide temperature range, and noise-immune receiver architecture for factory and infrastructure applications.

FAQ

What is the maximum signaling rate supported by SN65HVD74DR?

The SN65HVD74DR supports a maximum signaling rate of 20 Mbps under recommended operating conditions with a 54-Ω RS-485 load and 50-pF capacitance. This rate is validated across the full –40°C to +125°C temperature range and ensures compliance with TIA/EIA-485-A for high-speed deterministic communication in industrial networks. The SN65HVD74DR datasheet specifies typical rise/fall times of 4–7 ns and propagation delays of 4–20 ns at this rate.

Does SN65HVD74DR require external enable signals to operate?

No, SN65HVD74DR does not require external enable signals. It is a fully enabled transceiver with no DE (driver enable) or RE (receiver enable) pins - both driver and receiver are active whenever VCC is applied. This distinguishes it from SN65HVD70/73/76 variants and simplifies integration in always-on systems such as fixed-position PLC I/O modules or continuously logging e-meters where standby current is not a priority.

What package options are available for SN65HVD74DR?

SN65HVD74DR is offered in two industry-standard packages: 8-pin SOIC (D package, 4.90 mm × 3.91 mm) and 8-pin MSOP (DGK package, 3.00 mm × 3.00 mm). Both share identical pinout and electrical characteristics. The MSOP variant enables higher board density in space-constrained applications like DIN-rail mounted controllers or compact security system hubs, while the SOIC version supports legacy assembly processes and manual prototyping.

How does SN65HVD74DR handle electrostatic discharge events?

SN65HVD74DR provides >±12-kV IEC 61000-4-2 contact discharge protection on bus pins (A, B, Y, Z) and GND, plus >±30-kV HBM and >±4-kV IEC 61000-4-4 fast transient burst immunity. This eliminates the need for external TVS diodes in most industrial installations. The protection circuitry is integrated directly into the silicon, preserving signal integrity and avoiding added capacitance that could degrade 20-Mbps eye diagrams - a key advantage over discrete protection solutions.

What is the common-mode voltage range supported by SN65HVD74DR?

SN65HVD74DR supports a common-mode input voltage range of –7 V to +12 V on bus pins A and B, enabling reliable operation across ground potential differences up to 19 V between nodes. This specification allows deployment in electrically noisy environments such as motor control cabinets or multi-building campus networks where ground loops and induced surges are prevalent. The wide range is maintained across the full –40°C to +125°C operating temperature span.