Texas Instruments THVD1420DRLR

Overview

THVD1420DRLR from Texas Instruments is a half-duplex RS-485 transceiver in an 8-pin SOT package (2.1 mm × 1.2 mm), operating from 3.3 V to 5.5 V, supporting 12 Mbps data rate, ±12-kV IEC 61000-4-2 contact ESD protection, and -40°C to +125°C industrial temperature range. It enables robust serial communication in space-constrained factory automation and grid infrastructure nodes.

For engineers reviewing the THVD1420DRLR datasheet, THVD1420DRLR pinout, THVD1420DRLR application, or THVD1420DRLR equivalent, this page delivers verified electrical specs, validated bus-failsafe behavior, confirmed thermal shutdown operation at 150°C–170°C, and precise SOT-8 pin mapping for layout integration - all specific to THVD1420DRLR, not the THVD1400 variant.

Technical Context

The THVD1420DRLR implements a fully integrated half-duplex RS-485 transceiver with independent driver enable (DE) and receiver enable (RE) logic inputs, internal 2-MΩ pull-down on DE and pull-up on RE, and failsafe biasing that forces high output during open/short/idle bus conditions. Its differential driver delivers 1.5–3 V differential output voltage (|V_OD|) into 54 Ω, while the receiver features 30–50 mV hysteresis (V_HYS) for noise immunity.

It operates across full industrial ambient temperature (–40°C to +125°C), with thermal shutdown activation at 150–170°C and 15°C hysteresis. The device supports hot-plug operation via glitch-free power-up/down sequencing and meets TIA/EIA-485A electrical requirements including common-mode range (–7 V to +12 V) and 1/8 unit load (up to 256 nodes).

Key Specifications

Pinout & Package

THVD1420DRLR is packaged in an 8-pin SOT (DRL) with nominal body size 2.1 mm × 1.2 mm, optimized for ultra-compact PCB layouts. Pin numbering follows standard top-view orientation with Pin 1 at top-left corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN65HVD1420DR, THVD1420DRLR saves >70% board area with identical performance; versus THVD1450DRLR, it trades integrated regulation for 24× higher data rate and enhanced ESD robustness - making THVD1420DRLR optimal for space-constrained, high-speed industrial links.

Availability

THVD1420DRLR is available at Aetrix Electronics and suitable for factory automation, grid infrastructure, and motor drive applications requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for THVD1420DRLR 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, embedded processing, and connectivity solutions for industrial, automotive, and communications markets.

THVD1420DRLR belongs to TI's robust RS-485 transceiver portfolio, engineered specifically for high-noise, long-cable industrial networks demanding ESD resilience, thermal reliability, and ultra-compact packaging.

FAQ

What is the maximum data rate supported by THVD1420DRLR?

The THVD1420DRLR supports a maximum data rate of 12 Mbps, as specified in its switching characteristics table under recommended operating conditions. This performance is validated across the full –40°C to +125°C temperature range and into 54-Ω RS-485 loads. The THVD1420DRLR achieves this using optimized driver rise/fall times of 15–25 ns and propagation delays of 20–38 ns, distinguishing it from the 500-kbps THVD1400 variant.

Does THVD1420DRLR require external ESD protection on the bus lines?

No, THVD1420DRLR does not require external ESD protection on the A and B bus lines. It integrates ±12-kV IEC 61000-4-2 contact discharge and ±15-kV air-gap ESD protection directly on the bus pins, meeting industrial surge immunity requirements without added TVS diodes. This is confirmed in Section 5.3 of the official datasheet and eliminates BOM cost and layout area for discrete protection components.

What is the function of the RE and DE pins on THVD1420DRLR?

On THVD1420DRLR, RE (Receiver Enable) is an active-low input controlling receiver output state: when RE = low, R reflects the bus differential voltage; when RE = high, R enters high-impedance. DE (Driver Enable) is an active-high input: when DE = high, A/B drive the bus per D input; when DE = low, A/B enter high-impedance. Both pins feature internal pull resistors (2-MΩ pull-up on RE, pull-down on DE) for default safe states.

How does THVD1420DRLR handle open, shorted, or idle bus conditions?

THVD1420DRLR implements true failsafe receiver behavior: during open-circuit, shorted, or idle bus conditions, its receiver output R defaults to logic high. This is achieved via offset thresholds (V_IT+ = –70 mV, V_IT– = –200 mV, V_HYS = 30–50 mV), ensuring the indeterminate window excludes 0 V differential. The behavior is explicitly documented in Table 7-2 and Section 8.2.1.4 of the datasheet.

What package type is used for THVD1420DRLR, and what are its dimensions?

THVD1420DRLR uses the SOT-8 (DRL) package, with nominal body dimensions of 2.1 mm × 1.2 mm and 0.55-mm pitch. This ultra-compact footprint is confirmed in the Device Information table and Figure 4-1 of the datasheet. It is distinct from the SOIC-8 (D) variant and requires dedicated SOT-8 land patterns - not interchangeable with SOIC without redesign.