SNJ54HC259FK

Overview

The SNJ54HC259FK is an 8-bit addressable latch from the Texas Instruments SN54HC259 family, housed in a 20-pin Leadless Ceramic Chip Carrier (LCCC) package. It operates within a supply voltage range of 2 V to 6 V and supports an operating temperature range of -55°C to 125°C. The device features high-current inverting outputs capable of driving up to 10 LSTTL loads, with typical propagation delays of 14 ns. Key electrical characteristics include a maximum static current of 80 μA and ±4 mA output drive at 5 V.

Feature Summary

• Performs serial-to-parallel conversion by storing single-line data in eight individually addressable latches.
• Functions as a 1-of-8 decoder or demultiplexer with active-high outputs for signal routing.
• Includes an asynchronous parallel clear input to reset all outputs simultaneously.

Applications

• General-purpose storage applications in digital systems
• Working registers for temporary data holding
• Serial-holding registers for data buffering
• Active-high decoders or demultiplexers

Procurement Notes

Verify that the specific orderable part number matches the required military-grade qualification and lead finish specifications. Confirm the package type corresponds to the 20-pin LCCC form factor and ensure the temperature rating aligns with the -55°C to 125°C operational range defined in the datasheet before finalizing procurement.

Selection Notes

Select this component when designing systems requiring robust storage capabilities across extreme environmental conditions. The HC logic family offers low power consumption suitable for battery-operated devices, while the ceramic package provides enhanced durability for harsh environments compared to standard plastic packages.

Part Context

This device belongs to the SN54HC259 series, which are 8-bit addressable latches designed for general-purpose digital storage. The SNJ prefix indicates a military-grade version manufactured by Texas Instruments, distinct from the commercial SN74HC variants. It shares functional compatibility with other members of the HC/UH logic family.

Replacement Considerations

SNJ54HC259J

FAQ

What are the four distinct functional modes of the SNJ54HC259FK?

The device supports addressable-latch mode, memory mode, 1-of-8 decoding/demultiplexing mode, and clear mode, selectable via the CLR and G inputs.

How does the enable input affect operation?

The enable input simplifies expansion for n-bit applications and controls whether the addressed latch follows the data input or remains in its previous state during memory mode.