SN74HCT540N

Buffers, Drivers, Receivers, Transceivers Overview

The SN74HCT540N is an octal buffer and line driver with 3-state outputs manufactured by Texas Instruments. It operates within a supply voltage range of 4.5 V to 5.5 V and features low power consumption with a maximum ICC of 80 µA. The device provides ±6-mA output drive at 5 V and has inputs that are TTL-voltage compatible. Typical propagation delay (tpd) is 12 ns. It utilizes a data flow-through pinout arrangement where all inputs are on the opposite side from outputs, facilitating printed circuit board layout.

Buffers, Drivers, Receivers, Transceivers Feature Summary

• Octal buffers and line drivers designed for high-performance applications with inverted data outputs.
• Features a 3-state control gate using a 2-input NOR configuration for dual output-enable inputs.
• Data flow-through pinout places all inputs on the opposite side from outputs to facilitate PCB layout.
• High-current 3-state outputs can interface directly with system buses or drive up to 15 LSTTL loads.

Buffers, Drivers, Receivers, Transceivers Applications

• Direct interfacing with system buses
• Driving multiple LSTTL loads
• Memory address and data bus buffering

Buffers, Drivers, Receivers, Transceivers Procurement Notes

Verify the specific package type and temperature rating during procurement. The SN74HCT540N designation corresponds to the PDIP-20 tube package with an operating temperature range of -40°C to 85°C. Ensure compatibility with the required logic family and voltage levels before integration into the design.

Buffers, Drivers, Receivers, Transceivers Selection Notes

Select this component when an octal buffer with inverted outputs and 3-state capability is required. It is suitable for applications needing TTL-compatible inputs and direct bus interfacing. Consider the PDIP-20 package for through-hole mounting requirements and verify that the -40°C to 85°C temperature range meets the environmental specifications of the target application.

Buffers, Drivers, Receivers, Transceivers Part Context

The SN74HCT540N belongs to the HCT logic family, which combines CMOS technology with TTL-compatible input levels. It is part of the broader SN54/74HCT540 series, which includes variants in different packages such as SOIC and CDIP. This specific part number denotes the commercial grade version in a 20-pin PDIP package.

Buffers, Drivers, Receivers, Transceivers Replacement Considerations

SN74HCT540DW

Buffers, Drivers, Receivers, Transceivers FAQ

How does the 3-state control function work?

The 3-state control gate is a 2-input NOR. If either output-enable (OE1 or OE2) input is high, all eight outputs enter a high-impedance state.

What is the purpose of the pull-up resistor on OE?

To ensure the high-impedance state during power up or power down, OE should be tied to VCC through a pullup resistor.