SN74LS245N

Buffers, Drivers, Receivers, Transceivers Overview

The SN74LS245N is an octal bus transceiver utilizing Schottky transistor logic, designed for asynchronous two-way communication between data buses. It features eight non-inverting channels with three-state outputs capable of driving bus lines directly. The device operates within a supply voltage range of 4.75 V to 5.25 V and supports TTL input and output levels. Key electrical parameters include a maximum propagation delay of 12 ns at 45 pF load, a low-level output current capability of 24 mA, and a high-level output current of -15 mA. It functions in a commercial temperature range from 0°C to 70°C.

Buffers, Drivers, Receivers, Transceivers Feature Summary

• Three-state outputs allow direct connection to bus lines and provide isolation when disabled.
• PNP inputs reduce DC loading on the bus lines compared to standard NPN inputs.
• Built-in hysteresis at the bus inputs improves noise margins during signal transmission.

Buffers, Drivers, Receivers, Transceivers Applications

• Building automation systems
• Electronic point of sale terminals
• Factory automation and control networks
• Test and measurement equipment

Buffers, Drivers, Receivers, Transceivers Procurement Notes

Verify that the component matches the specific SN74LS245N designation rather than the industrial or military SN54LS245 variant, as operating temperature ranges differ. Confirm the package type is PDIP-20 and check for RoHS compliance status if required by assembly standards. Ensure the supplier provides documentation confirming the active production status and lead finish specifications.

Buffers, Drivers, Receivers, Transceivers Selection Notes

Select this component when designing systems requiring bidirectional data transfer between buses with moderate drive strength requirements. It is suitable for applications where TTL logic compatibility is necessary. Consider the thermal resistance characteristics for PCB layout planning. Evaluate the need for unused channel termination to prevent floating inputs in multi-channel implementations.

Buffers, Drivers, Receivers, Transceivers Part Context

This device belongs to the Texas Instruments SNx4LS245 family of octal bus transceivers. It shares functional pinouts and logic operations with other variants in the series but differs in manufacturing grade and environmental specifications. The SN74LS245N specifically denotes the commercial grade version housed in a plastic dual in-line package.

Buffers, Drivers, Receivers, Transceivers Replacement Considerations

SN74LS245DB

Buffers, Drivers, Receivers, Transceivers FAQ

How does the OE pin affect the device operation?

The Output Enable (OE) pin controls the state of all outputs. When OE is Low, the device is enabled and data transfers according to the DIR pin. When OE is High, all outputs enter a high-impedance state, effectively isolating the A and B buses.

What determines the direction of data flow?

The Direction Control (DIR) input determines the signal path. A High level on DIR allows data transmission from the A bus to the B bus, while a Low level allows transmission from the B bus to the A bus.