SNJ54BCT640J

Overview

The SNJ54BCT640J is an octal bus transceiver utilizing state-of-the-art BiCMOS technology, designed for asynchronous communication between data buses. It features bidirectional transmission controlled by a DIR input and isolation capability via an OE input. The device operates within the full military temperature range of -55°C to 125°C. Key electrical characteristics include a supply voltage (VCC) range of 4.5 V to 5.5 V, with high-level output current (IOH) up to -3 mA on Port A and -15 mA on Port B. Low-level output current (IOL) reaches 24 mA on Port A and 64 mA on Port B. Switching delays at VCC = 5 V and CL = 50 pF show tPLH/tPHL values ranging from 0.5 ns to 7 ns.

Feature Summary

• State-of-the-art BiCMOS design substantially reduces standby current consumption compared to standard TTL or CMOS equivalents.
• Outputs incorporate undershoot-protection circuitry to enhance signal integrity during transitions.
• Ensures a power-up high-impedance state to prevent unintended bus contention upon initialization.
• Buffered control inputs minimize DC loading effects on upstream logic drivers.

Applications

• Asynchronous communication interfaces between disparate data buses
• Military and defense electronic systems requiring extended temperature operation
• High-performance bus architectures needing low standby power

Procurement Notes

Verify that the specific ordering suffix corresponds to the Ceramic Dual In-line Package (CDIP) variant required for your application. Confirm that the component meets QML certification standards if intended for military or defense use cases. Ensure compatibility with existing board layouts regarding the 20-pin CDIP footprint dimensions and pin spacing specifications.

Selection Notes

Select this component when bidirectional data transfer is required across two separate bus structures with strict military temperature constraints. The BiCMOS technology offers a balance of speed and low power dissipation suitable for battery-operated or thermally sensitive environments. Consider the package options available, such as ceramic flatpacks or chip carriers, based on mechanical mounting requirements and thermal management needs.

Part Context

This part belongs to the SN54BCT640 family, which includes variants like the commercial SN74BCT640. The 'SNJ' prefix denotes a military-grade device in a ceramic dual in-line package. It serves as a bridge for data flow control in complex digital systems, distinct from unidirectional buffers or latches found in other logic families.

Replacement Considerations

Direct substitutes include SNJ54BCT640FK and SNJ54BCT640W, which share identical electrical characteristics but differ in package type (LCCC and CFP respectively). Verify pinout compatibility before substitution.