Texas Instruments DS36276M

Overview

DS36276M from National Semiconductor is a FAILSAFE multipoint transceiver for RS-485/RS-422 differential busses, featuring guaranteed HIGH receiver output under open, shorted, or terminated line conditions, ±7V to +12V common-mode range, and 5.0V supply operation. It serves as a robust interface between UART controllers and industrial multi-drop networks.

For engineers reviewing the DS36276M datasheet, DS36276M pinout, DS36276M application, or DS36276M equivalent, key selection criteria include fail-safe receiver behavior under fault conditions, bus voltage tolerance, driver/receiver enable independence, tri-state control timing, and SOIC-8 package compatibility with legacy transceivers.

Technical Context

The DS36276M implements a dual-function transceiver architecture with fully independent driver and receiver sections, each with dedicated enable controls (DE and RE). Its fail-safe receiver uses internal biasing to force RO = HIGH when differential input voltage |VID| < 200 mV - covering open-circuit, shorted, and 50Ω-terminated states.

It supports bidirectional half-duplex communication on shared differential pairs, meets TIA/EIA-485 and TIA/EIA-422-A electrical standards, and operates across −7V to +12V bus common-mode voltage while maintaining valid logic levels at RO. Driver output swing exceeds 1.5V differential under 54Ω load, and receiver hysteresis is 50 mV for noise immunity.

Key Specifications

Pinout & Package

DS36276M is housed in an 8-pin Small Outline Integrated Circuit (SOIC) package per NS Package Number M08A, with 1.27 mm pitch and standard JEDEC MS-012AC dimensions.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN75176B and MAX485CPA, DS36276M delivers deterministic fail-safe behavior without external components, higher ESD resilience, and identical SOIC-8 pinout - making it the preferred choice for industrial deployments requiring zero-failure bus initialization and fault recovery.

Availability

DS36276M is available at Aetrix Electronics and suitable for industrial PLC networks, building automation systems, and remote metering infrastructure requiring stable component supply, long-lifecycle support, and guaranteed fail-safe bus behavior.

Supply support for DS36276M 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

National Semiconductor was a U.S.-based analog and interface IC designer acquired by Texas Instruments in 2011; its legacy products remain widely deployed in industrial and communications systems.

The DS36276M belongs to National's RS-485 transceiver product line, engineered specifically for robust multi-drop serial communication in electrically harsh environments where bus fault resilience is mandatory.

FAQ

What does "FAILSAFE" mean for the DS36276M?

The FAILSAFE feature of the DS36276M guarantees that the receiver output (RO) remains HIGH when the differential bus inputs (A/B) are open-circuited, shorted together, or terminated with 50Ω - preventing undefined UART states. This behavior is built into the DS36276M's internal receiver bias network and requires no external components, unlike non-fail-safe transceivers such as SN75176B.

Is the DS36276M pin-compatible with other RS-485 transceivers?

Yes, the DS36276M is explicitly documented as pin-compatible with DS75176B, DS96176, DS3695, and SN75176A/B in its datasheet. All share the same SOIC-8 pinout (DI, RE, RO, DE, GND, A, B, VCC), enabling drop-in replacement in existing layouts - provided the fail-safe behavior of DS36276M aligns with system requirements.

What is the maximum data rate supported by the DS36276M?

The DS36276M supports data rates up to approximately 10 Mbps under ideal point-to-point conditions, based on its propagation delay (15–70 ns) and rise/fall times (12–50 ns). In real-world multipoint RS-485 networks with stubs and terminations, reliable operation is typically validated up to 2.5 Mbps - consistent with standard Modbus RTU and Profibus DP implementations using the DS36276M.

Does the DS36276M require external termination or bias resistors?

No, the DS36276M does not require external bias resistors to achieve fail-safe operation - its internal circuitry ensures RO = HIGH under open, shorted, or 50Ω-terminated conditions. However, standard RS-485 practice still applies: a single 120Ω termination resistor should be placed at each physical bus end, and the DS36276M itself does not integrate this function.

What is the operating temperature range for the DS36276M?

The DS36276M is specified for operation from 0°C to +70°C ambient temperature, as confirmed in its Recommended Operating Conditions table. This commercial-grade range suits indoor industrial control panels, building automation gateways, and point-of-sale equipment - but excludes extended-temperature applications such as outdoor metering enclosures without thermal management.