DM74ALS5245SJX

Overview

The DM74ALS5245SJX is an octal bus transceiver from the Advanced Low-power Schottky (ALS) logic family, manufactured by onsemi. It features a 20-lead Small Outline Package (SOP). The device supports asynchronous two-way communication between data buses with direction control via the DIR input and high-impedance isolation via the G input. Electrical specifications include a supply voltage range of 4.5V to 5.5V, low-level output current of 24mA, and high-level output current of -15mA. Propagation delay ranges from 3ns to 10ns.

Feature Summary

• Includes input hysteresis for improved noise rejection
• Configured for asynchronous bidirectional data bus communication
• Outputs enter high impedance mode when disabled

Applications

• Asynchronous two-way communication between data buses
• Memory systems
• Microprocessor systems

Procurement Notes

Verify that the ordering code suffix 'SJX' corresponds to the 20-lead SOP package variant as documented in the datasheet. Confirm the component status, as this specific part number may be discontinued or superseded by other manufacturers within the ALS family. Ensure compatibility with existing PCB footprints designed for the M20D package dimensions.

Selection Notes

Select this component for applications requiring robust noise immunity due to its integrated input hysteresis. The ALS technology offers a balance of speed and power consumption suitable for general-purpose digital logic. Verify that the required propagation delay falls within the specified 3ns to 10ns range for the target system clock speeds.

Part Context

This device belongs to the DM74ALS series, representing Fairchild Semiconductor's implementation of the Advanced Low-power Schottky TTL standard. The 'DM' prefix typically denotes commercial temperature grade variants. The 5245 designation specifically identifies the octal transceiver configuration within the broader 74ALS product line.

Replacement Considerations

SN74ALS5245NSR

FAQ

How is the data transmission direction controlled?

Direction is determined by the logic level of the DIR input; a LOW level transmits data from Bus A to Bus B, while a HIGH level transmits from Bus B to Bus A.

What mechanism isolates the buses?

The enable input (G) controls the isolation state. When G is HIGH, the outputs enter a high impedance mode, effectively disconnecting the buses.