SNJ54LS42FK

Signal Switches, Multiplexers, Decoders Overview

The SNJ54LS42FK is a high-reliability BCD-to-decimal decoder manufactured by Texas Instruments. It belongs to the SN54LS series, utilizing Low-power Schottky TTL technology for reduced power consumption and increased speed. The device features four binary inputs and ten active-low decimal outputs, providing one-hot decoding functionality. It is housed in a CQCC20 leadless ceramic chip carrier package, designed for military-grade environmental resilience. Key electrical specifications include a propagation delay of 30 ns and an operating supply voltage range of 4.75 V to 5.25 V.

Signal Switches, Multiplexers, Decoders Feature Summary

• Converts four-bit Binary Coded Decimal (BCD) input codes into ten mutually exclusive active-low decimal outputs.
• Utilizes Low-power Schottky (LS) TTL technology to achieve faster switching speeds with lower power dissipation compared to standard LS logic.
• Features inverted output logic levels, where the selected output line goes low while all others remain high.
• Constructed in a hermetically sealed leadless ceramic chip carrier package suitable for harsh environments.

Signal Switches, Multiplexers, Decoders Applications

• Military avionics systems requiring radiation-hardened or high-reliability logic components
• Spacecraft telemetry and command decoding circuits
• Industrial control systems operating under extreme temperature conditions
• High-reliability communication equipment signal routing

Signal Switches, Multiplexers, Decoders Procurement Notes

Verify the specific suffix 'FK' corresponds to the CQCC20 leadless ceramic package when sourcing. Confirm that the component meets military reliability standards if required for your application. Ensure compatibility with existing PCB footprints for ceramic chip carriers, as this package differs significantly from standard DIP or SOIC formats. Check for RoHS compliance status relative to your manufacturing regulations.

Signal Switches, Multiplexers, Decoders Selection Notes

Select the SNJ54LS42FK when a BCD-to-decimal decoder is needed for high-reliability applications. Choose this part over commercial variants if the design requires operation across extended temperature ranges or enhanced durability. Consider the CQCC20 package constraints during layout. Verify that the system can accommodate the 5V TTL logic levels and current requirements associated with the LS series.

Signal Switches, Multiplexers, Decoders Part Context

This component is part of the SN54LS family, which denotes military-grade performance and wider operating temperature ranges compared to the commercial SN74LS series. The SN54LS42 specifically implements the 4-line to 10-line decoding function. The 'FK' suffix identifies the specific leadless ceramic packaging variant within this logical family.

Signal Switches, Multiplexers, Decoders Replacement Considerations

• SN74LS42N
• SN74LS42AN

Signal Switches, Multiplexers, Decoders FAQ

What is the logic polarity of the SNJ54LS42FK outputs?

The outputs are active-low. When a specific BCD code is applied, the corresponding decimal output goes low, while all other outputs remain high.

How does the SNJ54LS42FK differ from the SN74LS42?

The SNJ54LS42FK is a military-grade device with guaranteed performance over a wider temperature range and higher reliability standards than the commercial SN74LS42. Additionally, the SNJ54LS42FK uses a ceramic chip carrier package, whereas the SN74LS42 is commonly available in plastic DIP packages.