Texas Instruments SN74AS760NSR

Overview

SN74AS760NSR from Texas Instruments is a dual 4-bit non-inverting open-collector buffer/line driver IC designed for bus-oriented memory address and clock distribution systems. It features two independent 4-bit channels, symmetrical active-low output-enable (OE) inputs per channel, pnp input structure for reduced DC loading, and supports 24 mA low-level output current at VCC = 4.5 V. It operates across 0°C to 70°C and drives TTL/CMOS-compatible loads in industrial control backplanes.

For engineers reviewing the SN74AS760NSR datasheet, SN74AS760NSR pinout, SN74AS760NSR application, or SN74AS760NSR equivalent, key selection criteria include open-collector drive capability, propagation delay under 19 ns, 5-V supply compatibility, dual-channel enable control, and SOP-20 package suitability for high-density PCB layouts with bus termination requirements.

Technical Context

This device implements two independent 4-bit non-inverting buffer sections, each with dedicated active-low output-enable (1OE, 2OE) controlling all four outputs simultaneously. Its pnp input stage minimizes DC loading on preceding logic, while open-collector outputs allow wired-AND bus interfacing and direct connection to pull-up resistors or external voltage rails up to 7 V.

Propagation delays are specified from A-to-Y (3–18.5 ns) and OE-to-Y (3–18.5 ns) under CL = 50 pF and RL = 500 Ω conditions. The device eliminates need for external 3-state overlap protection circuitry by ensuring controlled output disable timing, making it suitable for synchronous address/data bus drivers where glitch-free enable sequencing is critical.

Key Specifications

Pinout & Package

SOP-20 (NS) package: 20-pin surface-mount small-outline package with 0.635 mm lead pitch, 7.5 mm body width, and 2.65 mm max height. Pin 1 located at top-left corner with molded notch or beveled edge indicator.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal open-collector buffer applications.

Compared with SN74ALS760NSR, SN74AS760NSR delivers higher sink current and faster worst-case timing at the cost of increased ICC (94 mA vs. 32 mA); versus SN74AS244NSR, it trades tri-state flexibility for simplified bus arbitration and elimination of external protection logic.

Availability

SN74AS760NSR is available at Aetrix Electronics and suitable for industrial automation backplanes, legacy system upgrades, and test equipment clock distribution requiring stable component supply and long-term obsolescence management.

Supply support for SN74AS760NSR 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 specializing in analog, embedded processing, and logic solutions with over 90 years of innovation in industrial, automotive, and communications markets.

The SN74AS760NSR belongs to TI's advanced Schottky (AS) logic family, engineered for high-speed, high-drive bus interface applications where reliability, timing precision, and legacy compatibility are critical.

FAQ

What is the maximum sink current supported by each output of the SN74AS760NSR?

Each open-collector output of the SN74AS760NSR supports up to 64 mA of low-level output current (IOL) at VCC = 4.5 V, as specified in the electrical characteristics table. This rating ensures reliable driving of heavy capacitive loads, multiple TTL inputs, or bus termination networks without external amplification. The SN74AS760NSR maintains this performance across its full operating temperature range of 0°C to 70°C.

Does the SN74AS760NSR require external pull-up resistors on its outputs?

Yes, the SN74AS760NSR requires external pull-up resistors on all open-collector outputs (1Y1–1Y4 and 2Y1–2Y4) to establish defined high-level voltages. Pull-up values depend on bus capacitance and rise-time requirements; typical values range from 1 kΩ to 10 kΩ for 5-V systems. The SN74AS760NSR itself does not provide internal pull-ups and cannot drive high without external biasing.

Can the SN74AS760NSR be used as a direct replacement for the SN74LS244 in existing designs?

The SN74AS760NSR shares functional equivalence and pin compatibility with the SN74LS244 but differs in output type: SN74AS760NSR uses open-collector outputs, whereas SN74LS244 uses 3-state outputs. Direct replacement is feasible only if the target design accommodates open-collector operation (e.g., wired-AND buses with pull-ups). For tri-state bus architectures, SN74AS760NSR is not drop-in compatible without schematic modification.

What is the propagation delay variation between input-to-output and enable-to-output paths in the SN74AS760NSR?

The SN74AS760NSR exhibits matched propagation delays: tPLH/tPHL from A-to-Y and OE-to-Y are both specified from 3 ns (min) to 18.5 ns (max) under identical test conditions (VCC = 4.5–5.5 V, CL = 50 pF, RL = 500 Ω). This tight matching ensures predictable timing windows for enable-controlled data gating, eliminating setup/hold violations in synchronous bus systems using the SN74AS760NSR.

Is the SN74AS760NSR RoHS compliant and suitable for modern SMT assembly?

Yes, the SN74AS760NSR is RoHS compliant (lead finish: NIPDAU) and qualified for standard reflow soldering with MSL Level-1 rating (unlimited floor life at ≤30°C/60% RH). Its SOP-20 (NS) package features 0.635-mm pitch and 7.5-mm body width, supporting automated pick-and-place and reflow processes per IPC-7351 land pattern guidelines. Aetrix Electronics supplies fully traceable, production-grade SN74AS760NSR reels meeting J-STD-020 moisture sensitivity requirements.