DM74AS158N

Overview

The DM74AS158N is a quad 1-of-2 line data selector/multiplexer manufactured by onsemi (originally Fairchild) in the AS series. It features four independent multiplexers, each selecting between two inputs based on a common select line and an active-low strobe input. The device provides inverted outputs to minimize propagation delay time. It utilizes an advanced oxide-isolated, ion-implanted Schottky TTL process. The component operates within a supply voltage range of 4.5V to 5.5V and supports a free air operating temperature range of 0°C to +70°C.

Feature Summary

• Contains inverters and drivers for full on-chip data selection across four output gates.
• Features a separate STROBE input to control data routing functionality.
• Presents inverted data to the outputs to minimize propagation delay time.
• Functionally and pin-for-pin compatible with Schottky, low power Schottky, and advanced low power Schottky TTL counterparts.

Applications

• Multiplexing dual data buses
• Expanding any data input point
• Source programmable counters

Procurement Notes

Verify the specific package variant, as the N suffix denotes a 16-Lead Plastic Dual-In-Line Package (PDIP). Confirm RoHS compliance status through official documentation, as manufacturing sources may vary. Ensure the application environment remains within the specified 0°C to +70°C operating temperature range and that the supply voltage stays between 4.5V and 5.5V for reliable operation.

Selection Notes

Select this component when inverted logic levels are required at the output stage to optimize signal timing. It serves as a direct replacement for standard Schottky or Advanced Low Power Schottky equivalents requiring identical pinouts. Consider the improved AC performance characteristics over older TTL families if faster switching speeds are necessary for the target circuit design.

Part Context

This part belongs to the DM74AS family of high-speed logic devices. It is functionally paired with the DM74AS157, which provides true (non-inverted) outputs under identical conditions. Both devices share the same physical footprint and electrical interface specifications, differing only in the inversion state of their output signals.

Replacement Considerations

SN74AS158AN from Texas Instruments is a parameter-equivalent substitute.