DM74AS652WM

Overview

The DM74AS652WM is an octal bus transceiver and register from the AS series, manufactured by onsemi (formerly Fairchild Semiconductor). It features a 24-lead Small Outline Integrated Circuit (SOIC) package. The device operates with a supply voltage range of 4.5V to 5.5V and supports a maximum clock frequency of 90 MHz. Propagation delays are specified between 17 ns and 29 ns depending on the signal path. The component utilizes Advanced oxide-isolated, ion-implanted Schottky TTL technology.

Feature Summary

• Incorporates an octal D-type register for internal data storage alongside bidirectional bus transmission capabilities.
• Features totem-pole 3-STATE outputs designed to drive highly-capacitive or low-impedance loads directly without interface components.
• Includes select controls with a make-before-break configuration to eliminate glitches during transitions between stored and real-time data.

Applications

• Implementing buffer registers in digital systems
• Serving as I/O ports for microprocessor interfaces
• Functioning as bidirectional bus drivers
• Operating as working registers within memory architectures

Procurement Notes

Verify the manufacturer origin, as this part was originally produced by Fairchild Semiconductor before its semiconductor business acquisition. Confirm the specific package variant matches the design requirements, as the device is available in both SOIC and PDIP formats. Ensure the ordering code suffix aligns with the desired packaging type, such as tape and reel options if applicable.

Selection Notes

Select the DM74AS652WM when non-inverting output polarity is required for octal data transfer applications. This model differs from the DM74AS651, which provides inverted outputs. Consider the AS series performance characteristics regarding switching speed and drive capability compared to other logic families. Verify that the operating temperature range meets the system environmental specifications.

Part Context

This component belongs to the DM74AS651/DM74AS652 family of octal bus transceivers and registers. It shares functional similarities with the DM74ALS652 but offers higher speed performance typical of the AS series. The device is part of the broader 74-series logic ecosystem, providing compatibility with standard TTL input levels while utilizing advanced Schottky technology for improved switching characteristics.

Replacement Considerations

The DM74ALS652 serves as a lower-power alternative within the same functional category. For inverted output requirements, the DM74AS651 is the direct counterpart. Cross-reference pinouts and electrical characteristics carefully when substituting with devices from different manufacturers to ensure compatibility.