DM74AS245N

Overview

The DM74AS245 is an octal bus transceiver utilizing advanced Schottky TTL technology. It features eight pairs of three-state logic elements designed for asynchronous bidirectional data buses, memory, and microprocessor systems. The device operates within a supply voltage range of 4.5V to 5.5V and supports a free air operating temperature from 0°C to 70°C. Propagation delays are specified between 2ns and 7.5ns depending on the transition direction.

Feature Summary

• Advanced oxide-isolated, ion-implanted Schottky TTL process
• Three-state outputs independently controlled on A and B buses
• Low output impedance suitable for driving terminated transmission lines
• PNP inputs reduce input loading

Applications

• Memory systems
• Microprocessor systems
• Asynchronous bidirectional data buses

Procurement Notes

Verify the specific package variant (PDIP, SOIC, or SOP) required for the application. Confirm that the component meets the recommended operating conditions regarding supply voltage and temperature range. Ensure compatibility with CMOS interfaces if VOH specifications are critical. Check for tape and reel availability by appending the 'X' suffix to the ordering code.

Selection Notes

Select this component when high-speed switching and low output impedance are required for terminated transmission lines. The PNP input structure offers reduced loading compared to standard TTL. Verify interface requirements with CMOS devices, as the datasheet specifies guaranteed interfacing at VOH = VCC - 2V. Consider the thermal characteristics associated with the chosen package type.

Part Context

This device belongs to the AS series of octal bus transceivers. It provides non-inverting logic output and allows two-way communication controlled by the DIR input. The G enable input disables both driver and receiver outputs, placing them in a high-impedance mode to effectively isolate buses.

Replacement Considerations

Public confirmed substitute part numbers: SN74ALS245AN, SN74ALS245A-1N.