DM74LS670N

Overview

The DM74LS670N is a 3-state 4-by-4 register file organized as four words of four bits each. It features separate on-chip decoding for addressing word locations to write or retrieve data, allowing simultaneous read and write operations. The device operates with a supply voltage range of 4.75V to 5.25V and supports an operating temperature range of 0°C to +70°C. Propagation delays include typical values of 20ns for access time, 24ns for read time, and 27ns for write time.

Feature Summary

• Separate read and write addressing enables simultaneous reading from one location while writing to another.
• Expandable architecture allows up to 128 outputs to be wire-AND connected to increase capacity to 512 words.
• Individual address lines permit direct acquisition of data stored in any of the four internal latches.

Applications

• Scratch pad memory
• Buffer storage between processors
• Bit storage in fast multiplication designs

Procurement Notes

Verify the manufacturer origin, as this component was originally produced by Fairchild Semiconductor and may now be distributed by other entities such as onsemi. Confirm package integrity and pin alignment for the 16-Lead Plastic Dual-In-Line (PDIP) configuration before integration into the design.

Selection Notes

Select this component when a small, high-speed register file is required for parallel data handling. Ensure the system design accommodates the bipolar logic family characteristics and the specific voltage requirements of the LS series. Consider the expandability features if larger memory capacities are needed in future iterations.

Part Context

This part belongs to the 74LS logic family, known for low-power Schottky performance. It is functionally related to the DM74LS170 but offers 3-state outputs for bus applications. The PDIP package provides through-hole mounting options suitable for prototyping and legacy board designs.

Replacement Considerations

Direct substitutes include the SN74LS670N from Texas Instruments. Verify pin compatibility and electrical specifications before swapping manufacturers.

FAQ

Can the DM74LS670N perform read and write operations simultaneously?

Yes, the device features separate read and write addressing, which permits simultaneous reading from one word location while writing to another.

How can the memory capacity of this register file be expanded?

Up to 128 of these outputs may be wire-AND connected to increase the total capacity up to 512 words.