STMicroelectronics ST26C32ABN

Overview

ST26C32ABN from STMicroelectronics is a CMOS quad 3-state differential line receiver compliant with RS-422 and RS-423 standards, designed for balanced/unbalanced digital data transmission. It features ±0.2 V input sensitivity over ±7 V common-mode range, 19 ns typical propagation delay, 60 mV input hysteresis, and 3-state outputs with ±6 mA drive capability. Used in industrial serial communication interfaces where noise immunity and bus-sharing are required.

For engineers reviewing the ST26C32ABN datasheet, ST26C32ABN pinout, ST26C32ABN application, or ST26C32ABN equivalent, key selection considerations include differential input threshold stability across temperature, enable-controlled 3-state output behavior, RS-422/RS-423 compliance margin, and SO-16 package thermal performance in multi-receiver bus systems.

Technical Context

The ST26C32ABN implements four independent differential receivers with shared dual-enable control (pins 4 and 12), each providing TTL-compatible 3-state outputs. Input stage includes internal pull-up/pull-down resistors to suppress floating-channel oscillation and supports common-mode voltage from –7 V to +7 V.

It operates from 4.5 V to 5.5 V supply, delivers 10–20 Mbits/s data rate under 50 pF load, and exhibits 13–23 ns enable-to-output propagation delay. Input hysteresis (60 mV typ.) enhances noise rejection in electrically noisy industrial environments.

Key Specifications

Pinout & Package

ST26C32ABN is housed in a 16-pin SOIC (SO-16) surface-mount package with standard 1.27 mm pitch, JEDEC MS-012AC compliant footprint, and 1.75 mm height - suitable for automated assembly and thermal management in dense I/O modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar differential line receiver applications.

Compared with SN65LBC184DR and MAX3080CSA+, the ST26C32ABN offers superior bus-sharing flexibility via dual ENABLE pins and built-in channel biasing - reducing external component count in modular industrial backplanes where channel utilization varies per configuration.

Availability

ST26C32ABN is available at Aetrix Electronics and suitable for industrial PLC backplane interfaces, factory automation serial buses, multi-protocol communication gateways, and ruggedized data acquisition nodes requiring stable component supply across extended product lifecycles.

Supply support for ST26C32ABN 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, delivering intelligent power, sensing, connectivity, and microcontroller solutions for automotive, industrial, and consumer markets.

The ST26C32ABN belongs to ST's industrial interface IC portfolio, engineered specifically for robust, low-power differential communication in harsh electromagnetic environments - emphasizing reliability, long-term availability, and compliance with legacy industrial standards.

FAQ

What is the maximum common-mode voltage the ST26C32ABN can tolerate during normal operation?

The ST26C32ABN supports a continuous input common-mode voltage range of ±7 V under recommended operating conditions (VCC = 4.5–5.5 V, TA = –40 to +85 °C). Absolute maximum rating extends to ±14 V, but sustained operation beyond ±7 V may degrade noise immunity or trigger latch-up if not properly clamped externally.

Does the ST26C32ABN require external pull-up or pull-down resistors on its differential inputs?

No. The ST26C32ABN integrates internal pull-up and pull-down resistors on all input terminals to prevent floating states and output oscillation on unused channels. This eliminates the need for external biasing components in partial-bus or configurable I/O designs, reducing BOM count and layout complexity.

Can the ST26C32ABN operate with a 3.3 V supply?

No. The ST26C32ABN is specified only for 4.5 V to 5.5 V operation. At 3.3 V, internal CMOS logic thresholds are not met, resulting in undefined output states, increased propagation delay (>50 ns), and failure to meet RS-422 input sensitivity requirements. A level-shifting interface or alternate 3.3 V–compatible receiver (e.g., MAX3080) is required.

How does the dual ENABLE pin configuration improve system reliability?

The dual ENABLE pins (4 and 12) must both be driven high to activate all four receivers. This design prevents accidental enable due to single-point noise glitches or trace coupling. In safety-critical systems, it allows redundant control paths - e.g., one pin driven by MCU GPIO and the other by hardware watchdog - ensuring fail-safe bus disconnection during faults.