Texas Instruments SN74LS468DW

Overview

SN74LS468DW from Texas Instruments is an octal buffer with 3-state outputs, designed for bidirectional data bus interfacing in TTL systems. It features active-low output-enable (OE̅), complementary true/inverted outputs per channel, and operates at VCC = 5 V with typical propagation delay of 15 ns and fan-out of 20 LS-TTL loads.

For engineers reviewing the SN74LS468DW datasheet, SN74LS468DW pinout, SN74LS468DW application, or SN74LS468DW equivalent, key selection considerations include 3-state bus driving capability, dual-output polarity per channel, DC noise margin of 0.4 V (min), and SOIC-24 package compatibility with legacy 74LS logic layouts.

Technical Context

The SN74LS468DW integrates eight independent buffer channels, each with true (Y) and complement (W) outputs controlled by a shared active-low output-enable input (OE̅). All inputs are TTL-compatible with VIH = 2 V (min) and VIL = 0.8 V (max), and outputs drive ±8 mA at VOH/VOL specifications.

It belongs to the 74LS family and maintains full compatibility with standard 74LS logic levels and timing. The device supports high-speed bus isolation in microprocessor systems where simultaneous read/write control and signal inversion are required without external inverters.

Key Specifications

Pinout & Package

SN74LS468DW is housed in a 24-pin SOIC (Small Outline Integrated Circuit) package with 300-mil body width and standard pin pitch of 0.050 inch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal 3-state buffer applications.

Compared with SN74LS244N and SN74LS245N, the SN74LS468DW uniquely delivers true and complement outputs per channel in a fixed-function 24-pin SOIC package-enabling simpler bus interface designs where both signal polarities are required without added components or control logic.

Availability

SN74LS468DW is available at Aetrix Electronics and suitable for microprocessor bus interfaces, industrial PLC backplanes, legacy system upgrades, and automated test equipment requiring stable component supply and long-term obsolescence management.

Supply support for SN74LS468DW 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 and automotive reach.

The SN74LS468DW belongs to TI's legacy 74LS logic family, engineered for robust, low-power TTL-compatible interfacing in commercial-grade digital systems requiring reliability and long-lifecycle support.

FAQ

What is the function of the W outputs on the SN74LS468DW?

The W outputs on the SN74LS468DW provide logic-complemented versions of each corresponding Y (true) output. For every input A1–A8, W1–W8 deliver inverted signals simultaneously-eliminating the need for external inverters in applications requiring both polarities, such as differential bus signaling or dual-phase control logic. This dual-output architecture is intrinsic to the SN74LS468DW design and fully operational when OE̅ is asserted LOW.

Does the SN74LS468DW support bidirectional data flow like the SN74LS245?

No, the SN74LS468DW does not support bidirectional data flow. It is a unidirectional octal buffer with fixed input-to-output signal path (A → Y/W). Unlike the SN74LS245, it lacks a direction-control input and cannot reverse data flow. Its role is strictly to buffer and replicate (with inversion) signals from inputs to outputs under OE̅ control-making the SN74LS468DW ideal for static polarity requirements, not dynamic bus direction switching.

What is the recommended operating voltage range for the SN74LS468DW?

The SN74LS468DW is specified for operation at VCC = 5 V ±5%, i.e., 4.75 V to 5.25 V. Operation outside this range may cause timing violations, reduced noise margin, or output drive degradation. The device draws ICC = 60 mA typical at 5 V and is not rated for 3.3 V or mixed-voltage operation. Designers must ensure clean, regulated 5 V supply with adequate decoupling near the SN74LS468DW VCC and GND pins.

Can the SN74LS468DW replace the SN74LS244 in an existing design?

The SN74LS468DW can replace the SN74LS244 in many cases but requires validation of pin mapping and functional intent. While both are octal 3-state buffers, the SN74LS468DW offers dual (Y/W) outputs per channel versus single outputs on the SN74LS244, and uses a 24-pin SOIC versus 20-pin PDIP. Direct replacement is feasible only if the PCB accommodates the larger package and the design leverages or ignores the W outputs-otherwise, signal routing and enable logic must be reviewed before substitution.

Is the SN74LS468DW suitable for use in automotive applications?

No, the SN74LS468DW is not qualified for automotive applications. It is rated for commercial temperature range (0°C to +70°C) and lacks AEC-Q100 qualification, extended temperature grading, or automotive-specific reliability testing. Texas Instruments explicitly restricts its use in safety-critical or life-support systems. For automotive designs, engineers should select AEC-Q100-qualified alternatives such as the SN74LVCH16244A or automotive-grade variants of the 74LVC family-not the SN74LS468DW.