Texas Instruments SN74ALS29827DW

Overview

SN74ALS29827DW from Texas Instruments is a 10-bit non-inverting buffer/bus driver with dual 3-state enable inputs (OE1, OE2), SOIC-24 package, operating at 4.75–5.25 V, delivering ±24 mA output drive, and rated for 0°C to 70°C industrial temperature range. It interfaces wide data buses or memory address registers in legacy computing and industrial control systems.

For engineers reviewing the SN74ALS29827DW datasheet, SN74ALS29827DW pinout, SN74ALS29827DW application, or SN74ALS29827DW equivalent, key selection criteria include true-output logic polarity, dual-NOR 3-state control architecture, pnp input structure reducing DC loading, data flow-through pinout, and high-impedance power-up state.

Technical Context

The SN74ALS29827DW implements a dual-input NOR gate for 3-state control: either OE1 or OE2 high forces all ten Y outputs into high-impedance. Its pnp-based ALS (Advanced Low-Power Schottky) input stage minimizes DC current draw on driving sources, critical in bus-loaded systems.

It features a symmetric, flow-through pinout-A1–A10 on one side, Y1–Y10 on the opposite-with GND and VCC centrally located. Propagation delays are 7–15 ns (CL = 50–300 pF), and enable/disable times range from 9 ns (CL = 5 pF) to 23 ns (CL = 300 pF), supporting reliable timing in synchronous bus architectures.

Key Specifications

Pinout & Package

SN74ALS29827DW uses a 24-pin SOIC (DW) package, 300-mil body width, with gull-wing leads and RoHS-compliant NiPdAu finish. Pin 1 is OE1, pin 13 is GND, pin 14 is VCC, and pins 15–24 and 1–10 carry outputs and inputs respectively in flow-through arrangement.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit non-inverting bus driver applications.

Compared with SN74ALS29828DW and AM29827, the SN74ALS29827DW provides guaranteed true-output behavior and TI's documented ALS process consistency, making it preferred for new designs requiring verified non-inverting bus buffering with industrial temperature support.

Availability

SN74ALS29827DW is available at Aetrix Electronics and suitable for memory address buffering, parallel bus isolation, and legacy system upgrade interface applications requiring stable component supply and long-term industrial availability.

Supply support for SN74ALS29827DW 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 U.S.-based semiconductor company founded in 1930, specializing in analog, embedded processing, and logic ICs with broad industrial, automotive, and communications product portfolios.

The SN74ALS29827DW belongs to TI's legacy Advanced Low-Power Schottky (ALS) logic family, designed specifically for high-speed, low-power 5 V bus interfacing in computing and industrial control systems of the 1980s–1990s.

FAQ

What logic function does the SN74ALS29827DW implement?

The SN74ALS29827DW implements a 10-bit non-inverting buffer with dual 3-state enable inputs (OE1 and OE2). Its outputs Y1–Y10 replicate inputs A1–A10 when both enables are low; either OE1 or OE2 high places all outputs in high-impedance. This functionality is confirmed in the TI SDAS095B datasheet and distinguishes SN74ALS29827DW from the inverting SN74ALS29828DW variant.

What is the recommended operating voltage range for the SN74ALS29827DW?

The SN74ALS29827DW is specified for operation from 4.75 V to 5.25 V. This 5 V ±5% range ensures compatibility with standard TTL/ALS logic families and accounts for typical power supply ripple and tolerance. Operation outside this range risks incorrect logic levels or device damage, as absolute maximum VCC is 7 V per the datasheet.

Does the SN74ALS29827DW have a power-up high-impedance state?

Yes, the SN74ALS29827DW enters a high-impedance state at power-up before enable signals stabilize. This behavior is explicitly documented in the "Features" section of the SDAS095B datasheet and prevents bus contention during system initialization - a critical requirement in multi-master bus architectures where SN74ALS29827DW is commonly deployed.

What package type and pin count does the SN74ALS29827DW use?

The SN74ALS29827DW uses a 24-pin SOIC (DW) package with 300-mil body width, gull-wing leads, and RoHS-compliant NiPdAu plating. This is confirmed in TI's Packaging Information Addendum and matches the top-view pin diagram showing OE1 at pin 1, GND at pin 13, VCC at pin 14, and Y1–Y10 distributed across pins 15–24 and 1–10.

How does the pnp input structure of the SN74ALS29827DW benefit system design?

The pnp input structure of the SN74ALS29827DW reduces DC input current to ≤0.1 mA, lowering loading on upstream drivers by over 90% compared to standard TTL inputs. This allows higher fanout - up to 20+ devices - without intermediate buffering, simplifying board layout and improving signal integrity in bus-critical applications like memory address distribution where SN74ALS29827DW is routinely applied.