STMicroelectronics ST1480ACDR

Overview

ST1480ACDR from STMicroelectronics is a 3.3 V powered, half-duplex RS-485/RS-422 transceiver with ±15 kV HBM ESD protection, guaranteed 12 Mbps data rate, and industry-standard 75176 pinout. It integrates one driver and one receiver, supports -7 to +12 V common-mode input range, and features true fail-safe receiver operation for floating or shorted bus lines - used in industrial automation serial backbones.

For engineers reviewing the ST1480ACDR datasheet, ST1480ACDR pinout, ST1480ACDR application, or ST1480ACDR equivalent, key selection criteria include shutdown current (≤1 µA), differential output voltage (≥1.5 V into 54 Ω), receiver input resistance (24 kΩ), thermal shutdown protection, and interoperability with 5 V logic interfaces.

Technical Context

The ST1480ACDR implements a half-duplex transceiver architecture with independent driver enable (DE) and receiver enable (RE) controls, enabling precise bus arbitration. Its driver uses current-limiting and thermal shutdown circuitry to prevent damage during bus contention or short-circuit events.

The receiver incorporates true fail-safe biasing: RO outputs high when A and B are open, shorted, or terminated with no signal - eliminating need for external bias resistors. Input hysteresis (30 µV) ensures noise immunity across the full -7 to +12 V common-mode range.

Key Specifications

Pinout & Package

ST1480ACDR is housed in an SO-8 package (8-pin small outline integrated circuit) with ECOPACK® environmental compliance and 2500 units per tape-and-reel reel.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX13487EESA+ and SN65HVD72DR, ST1480ACDR uniquely balances 64-node bus support, true fail-safe operation, and explicit DE/RE control - making it optimal for deterministic industrial networks where bus topology flexibility and robust idle-state behavior are mandatory.

Availability

ST1480ACDR is available at Aetrix Electronics and suitable for industrial PLC backplanes, smart sensor nodes, motion control networks, and energy meter data concentrators requiring stable component supply across extended product lifecycles.

Supply support for ST1480ACDR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

The ST1480ACDR belongs to ST's high-reliability RS-485 transceiver product line, engineered specifically for noise-immune, long-distance industrial communications with emphasis on ESD robustness, bus scalability, and fail-safe behavior in unpowered or faulted conditions.

FAQ

What is the maximum common-mode voltage range supported by ST1480ACDR?

The ST1480ACDR supports a common-mode input voltage range of -7 V to +12 V, enabling reliable operation despite ground potential differences up to 19 V between connected nodes. This specification is validated per ANSI/TIA-485-A and confirmed in Table 8 of the official datasheet (DocID9101 Rev 5, p.7). It ensures stable receiver performance in electrically noisy factory environments with long cable runs and multiple grounding points.

Does ST1480ACDR require external bias resistors for fail-safe operation?

No, ST1480ACDR features true internal fail-safe biasing that guarantees a logic-high RO output when the A and B lines are open-circuited, shorted together, or terminated with no active driver - without any external resistors. This is implemented via on-die precision bias circuitry and verified in the functional description (p.1) and truth table (Table 3) of the datasheet. It eliminates BOM cost and layout complexity associated with discrete bias networks.

How does the shutdown mode function, and what is its current draw?

Shutdown mode is activated by setting RE = high and DE = low simultaneously, placing both driver and receiver outputs in high-impedance state while reducing supply current to ≤1 µA (typical 0.002 µA). The device exits shutdown within 35 ns (tZL(SHDN)) for driver and 20 µs (tZL(SHDN) receiver) after valid DE/RE transitions. This behavior is documented in Table 9 and Table 10 (p.7–8) and confirmed in the functional description (p.1).

Can ST1480ACDR interface directly with 5 V logic controllers?

Yes, ST1480ACDR accepts 5 V-tolerant logic inputs on DE, RE, and DI pins - with VIH(min) = 2.0 V and VIL(max) = 0.8 V - allowing direct connection to 5 V microcontrollers without level shifters. This interoperability is specified in Table 6 (p.6) and emphasized in the Features list (p.1). The device operates from a 3.3 V supply while maintaining full logic compatibility with legacy 5 V systems.